eBay

eBay is a marketplace, so there is no single house price. The saving comes from choosing the right listing, and eBay's own promotions sit on top of that.

Sort by price plus shipping. The default sort mixes sponsored and popular listings. Sorting by "Price + Shipping: lowest first" removes the two most common ways an eBay bargain turns out not to be one: a low headline price with heavy postage, and a listing for a part or accessory that matched your search.

Check the seller before the price. Feedback score and percentage, how long the account has existed, and whether the item is covered by the eBay Money Back Guarantee. On electronics, "eBay Refurbished" listings come from vetted sellers with a warranty and a return window, and are usually the safest way to take a large discount.

Coupons. eBay issues site-wide codes a few times a year, typically a percentage off with a cap and a minimum spend, and applies them at checkout in the "Add coupons" box. Seller coupons and "Buy 2, get 1" style multi-buy offers are set per seller and show on the listing. Codes that circulate on coupon sites are very often expired or single-use; treat any eBay code as unverified until it lowers your total.

Best Offer. Many listings accept offers. A polite offer of 10 to 15% under asking is accepted often enough to be worth the thirty seconds it takes.