These eBay Bucks offers are targeted and you need to receive the email or have it in your eBay account in order to qualify. Rewards are capped at $100 per transaction and $500 per Earn Period. Purchases must be completed during the Promotion period and paid for with PayPal before the Promotion ends.
You can stack this with cashback from shopping portals. TopCashBack is offering 2% cashback on eBay purchases, but make sure you read exclusions in fine print.
The Promotion starts at 5:00AM PT on August 10, 2017, and ends at 11:59PM PT on August 11, 2017 (the “Promotion Period”). Extra eBay Bucks can only be earned on every single item purchased that meets the minimum purchase requirement specified in the offer (a “Qualifying Purchase”). Promotion is valid on multiple qualifying purchases made within the promotion time period. In order to qualify for the offer, you must click the email to activate.
Qualifying purchase excludes all items in the following categories: Classifieds, Business & Industrial, but only for Heavy Equipment within that category, Real Estate, Gift Cards & Coupons (including eBay Gift Cards, Gift Cards, and Digital Gifts within that category), Bullion (within the Coins & Paper category), and all categories in Motors, except Parts & Accessories.