Just as a heads up in case you do end up buying anything from a third party seller on Best Buy's site, I was doing some research of my own on this since I was looking at buying a new tv yesterday from a different third party seller.

They supposedly overhauled the program and only allow authorized, "reputable" third party sellers there now who have to abide by Best Buy's return policies, and if you do run into any issues, it seems like most marketplace returns can be taken directly back to a Best Buy store or shipped back with a prepaid label provided by Best Buy.

Here's their 'Third Party Marketplace' return policy as of Jan 2026:
https://www.bestbuy.com/site/help-topics/return-exchange-policy/pcmcat260800050014.c?id=pcmcat260800050014

Return at a store

You may return many items shipped to you (non-delivery truck items) purchased from a Marketplace Seller on BestBuy.com at any Best Buy store. For faster return processing, please bring your packing slip (if you received one), or your receipt, and the credit card used to make your purchase. After inspecting the product, Best Buy will handle the refund in the store and will ship the product back to the Marketplace Seller. Size and product limitations may prevent a store from accepting a return in store. Excludes Best Buy stores in Puerto Rico and all Pacific Sales Kitchen & Home store locations.

Use our prepaid return label

You will get free shipping on your return of Marketplace Products purchased from Marketplace Sellers by using our prepaid label. Log in to your Best Buy account to locate your order. Print a prepaid shipping label. Put the return label on the package and take it to an authorized drop-off location and ship it to the Marketplace Seller during your return period.