AuctionNinja | Knowledge

Basic Auction

What is a buyer's premium?

A buyer's premium is a percentage-based fee added to the winning hammer price. This helps cover the auctioneer’s expenses and administrative costs and off-sets credit card fees. The larger auction houses in major cities sometimes charge up to a 30% buyer's premium. Bidders may also be charged sales tax (depending on regulations of the individual state where the auction is held) on this additional fee.

Here’s an example ...
If you won an auction lot through “A-Z Auctioneers” with a 15% buyer’s premium and 5% state sales tax (the buyer’s premium is often taxed, but laws vary by state) here’s how it would work out:

Hammer Price


Buyer’s Premium (15%)


State Sales Tax (5%)




You should note that buyer’s premiums vary depending on the individual auctioneer / estate seller using the AuctionNinja platform. Please be sure to read the terms for each individual sale. If you have questions about a buyer’s premium, please contact the auction house / estate seller directly. AuctionNinja does not control what individual sellers charge for their buyer’s premiums.



What is extended bidding?

The AuctionNinja platform features extended bidding (a.k.a. "soft closing"). The AuctionNinja system will automatically extend the closing time of a lot (auction item) whenever a bid is placed within the last five minutes of its scheduled closing. This may occur multiple times on any given lot depending on the bidder interest in that lot. Once all interest and bidding in a lot ceases the clock will run out and the lot will close.

This is the fairest way to prevent “bid sniping” (someone submitting a high bid in the last seconds of any given lot’s closing in order to win said lot) and to give all bidders an opportunity to increase their bids if they wish. It is also the closest way to mimic a live, in-person auction, when the auctioneer gives bidders opportunities to increase their bids if someone jumps into the bidding at the last moment before hammering the winning bid. 


Sometimes I'm immediately outbid. Why?

Because all maximum bids are "masked" (hidden from other bidders), you do not know what any other bidder's maximum bid may be or when they placed it. Sometimes you will be outbid as soon as you enter your bid. This only occurs when another bidder had a higher maximum bid than yours already "on the board". Your bid set in motion BRG's automatic bidding system which raised the other buyer's bid above yours. The other bidder may have placed their max bid days, hours, or mere moments before you placed yours. 

However, if you place a bid and there are no competing bids against your bid, the system WILL NOT immediately go to your maximum bid. In fact, if you are the only bidder by the time the lot closes, you will win the lot for the lowest possible dollar amount (based on whatever the opening bid was for that item), not your max bid. So if you place a max bid of $25 on a lot with an opening bid of $1 and there are no other bidders vying for that lot, you will win it for $1. NOTE: This only happens when there are no competing bids.


Why was I outbid by an amount less than the next minimum increment?

Occasionally our bidders are outbid by an amount lower than the minimum bid increment (see bid increments in our Terms & Conditions). All bidders may place their max bid at anytime.  As a result, you may be outbid by what seems to be an incorrect increment.  The AuctionNinja system will not default to strict increments like a traditional auction if an "odd" maximum bid was left prior to meeting the bid price which would engage the next bid increment. 

For example, let's say you place your maximum bid of $100 on a painting but another buyer wins the lot for $101. As stated in the bidding increments, you know the next bid should have been $105, not $101. The system will accept the $101 bid because that max bid of $101 was placed before the auction got to that next increment level.

Here's how: It's 4 p.m. on closing day and the painting is currently at $15. At 5:10 p.m. you place a maximum bid of $100. There are a few bidders at play and so by the time 5:45 comes around, the current bid is at $78 with you as the highest bidder.  At 7:05 p.m. a new bidder joins in and places his maximum bid of $101. Since this new bidder's bid of $101 is above the minimum increment at the time she placed the bid, it is accepted by the system. Since there were no additional bids placed before the countdown clock ran out, the $101 bidder wins the lot because it is higher than your $100.


My max bid was the same as the winning bid (tie bid), yet someone else won it. Why?

In the case of a tie bid, the hammer will always fall to the first bidder. For example, the current bid is $50 (placed by someone else). What you don't know is that their max bid (which is masked from other bidders) is $200. You join the bidding and and place a maximum bid of $200 and are immediately outbid in favor of the other bidder. Even though two people have the same max bid, only one person can win the lot. That is automatically determined by bidding order -- the person who placed that maximum bid first.


Post Auction

Can I pay by cash or check at pick-up?


In order to keep AuctionNinja uncomplicated for sellers and bidders, the only method of payment accepted is credit card via auto-debit at the close of the auction. This makes it easy for bidders to simply show-up at the designated location and pick-up their items. It also is safer and more secure for our auctioneers/sellers who, otherwise would be concerned about holding large sums of cash on hand.


Do you ship?

Again, AuctionNinja is merely the bidding platform bringing together buyers and sellers. You must contact the individual auction house / estate seller regarding shipping options (if they even offer any). Many sellers only offer local pick-up, but sale terms vary depending on the individual seller. Often these details are located on the landing page for each auction. Please be sure to read the auction terms for each auction before bidding, too. 


I won an item in an auction, what now?

Within two hours of the close of the entire auction your credit card on file will be charged for the entire amount due (hammer price + sales tax + buyers premium). The charges are not processed until the entire auction closes. You will also receive a winning bidder email which will list your invoice (what item(s) you won, the hammer price, sales tax, and buyers premium) and all necessary pick-up instructions. Note the pick-up instructions are also always viewable on the auction landing page. Any questions about the auction results and/or pick-up instructions should be directed to the individual vendor/seller (details for the seller may be found on the auction landing page).


I won some items, where do I pick them up?

The individual auction vendor will feature pick-up details on the landing page for each of their auctions  Sometimes, in the case of a residential estate location, the actual address will be included in the winning email (not included on the landing page) which is sent to the email address on file with your account. Please be sure to read the auction terms for each auction before bidding, too, to make sure that you are available to pick-up your items during the designated dates/times. Most often there are no other pick-up options available and requests for alternative pick-up options are at the sole discretion of the individual auction vendor.


What if I have a last minute emergency?

We understand that life throws curveballs sometimes. AuctionNinja is a bidding platform whereby individual auction houses and estate sellers sell their merchandise, so AuctionNinja has no input in the pick-up arrangements made by vendors. Alternate arrangements are at the sole discretion of the auctioneer per their auction terms. If you have a true emergency and cannot follow through on the auction pick-up terms for bidding, please contact the individual AuctionNinja seller/auctioneer (info found on individual auction listing pages). They may be in a position with their consignors to make alternate arrangements, but the majority of time your items will be considered forfeit.


I am the winning bidder and now realize that I don’t want my items. That’s ok, right?

In short, no. No, it’s not ok. When you bid on any items in an auction, it’s a legally binding agreement to purchase the item(s) if you are the winning bidder. Once the auction closes, if you’re the high bidder, per the terms of use / bidder agreement, you are obligated to follow-through on your purchase. Auctions do not work like retail stores where you can return an item if you have “buyers remorse.” So you must be sure that you are able to uphold your end of the agreement before placing your bid(s). You must do your own "due-diligence" in researching the items you plan to bid on -- before bidding -- per the terms of bidding. Items are sold "AS-IS, WHERE-IS," meaning there are no guarantees, warrantees, etc. Reneging on your agreement as the winning bidder in any auction will result in the permanent revocation of your bidding privileges on the AuctionNinja platform.



What is my dashboard?

Your personal, password-protected dashboard allows you to track your bidding history, favorite lots, and more. The dashboard is essentially your account profile. From your dashboard, you may update your personal information at any time -- including billing address, credit card, etc. You may view your consignments with individual vendors (if you're a consignor) and/or your past purchased. Additionally, if you're following several lots from a variety of vendors, you may manage your bids directly from your dashboard vs. trying to watch multiple auctions simultaneously. In other words, manage your bidding on only those specific lots in which you are interested.


How do I update my credit card?

Cards expire or perhaps you may have gotten an entirely new card. Changing your card is easy on AuctionNinja. You may change your default credit card details at any time by logging onto AuctionNinja.com. Click on MY DASHBOARD. Then click on ACCOUNT. Click on BILLING OPTIONS. Next to “Manage Payment Options” click on +ADD CREDIT/DEBIT CARD (in red) and enter your new card info. Voila! Your new card is set.


How do I update my state tax certification / reseller certificate?


  Changing/adding your reseller tax ID certificate is easy on AuctionNinja. You may update your information at any time by logging onto AuctionNinja.com. Click on MY DASHBOARD. Then click on ACCOUNT. Click on PREFERENCES. Check the box next to TAX INFORMATION. Enter your TAX ID # and be sure to upload a copy of the certificate.

***IMPORTANT: You must include a copy of the certificate in order for your Tax ID to be valid. Providing your Tax ID number only is not enough. It must be accompanied by the certificate. Contact and address information must also match the information on the certificate.***


Why do I need to add my tax exempt/resellers certificate for each company I bid with?

Since AuctionNinja is a bidding platform licensed by individual vendors, they are required to maintain their own set of client reseller certificate records (for IRS and state tax purposes). If they get audited, they need to produce their own documentation. As a result if you are a bidder and have a tax exempt / reseller's certificate, you need to submit that to the individual vendor/licensee. That means, if you bid in three auctions offered by three different vendors, you will need to submit your resellers certificate to each vendor. 



How can I opt-in to receive AuctionNinja sale notifications in my area?

You may opt-in to receive email notifications about sales powered by AuctionNinja by clicking "Sign Up" in the menu bar.


How do I build my own newsletter options?

The AuctionNinja platform allows you to customize the information you recieve about vendor sales. You may do this with the "Build Your Newsletter" option. To access this, simply login to your dashboard. Hover over the "Your Account & Bids" menu tab and select "Build Your Newsletter" in the drop down box. From here you can filter the vendors you see by state and a zip code radius.

You will see all the current licensees/vendors who are located within your parameters. Simply click the heart icon in each vendor's box to either follow or unfollow that specific vendor (gray heart is unfollow, red heart is follow). You will then only receive emails when there are sales provided by those vendors you follow.

Be sure to periodically update your choices, as new licensees/vendors register and you may want to follow their sales too.



I'm moving/downsizing/having a tag sale. Can I list my sale with AuctionNinja?

In short, the AuctionNinja online auction software subscription is meant for estate sale professionals or auctioneers. So no, you will not be able to list or sell your individual sale directly on AuctionNinja. You may, however, contact any of the AuctionNinja vendors who service your region to inquire whether or not they might be able to help you sell your personal property items. Take a look at our AuctionNinja Nation blog for an updated list of vendors who use AuctionNinja throughout the country.

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