If you like to shop for beauty deals on Amazon, I found a deal for a bottle of Wet n Wild primer serum. It's on sale for $6.99 (usually $7.99), but you'll get a better deal when you clip the coupon for 25% off.
Then, be sure to check out with Subscribe & Save for 5% or 15% off. If you subscribe to five eligible items or more, you'll get the maximum 15% discount. So you could pay as little as $4.19 for one bottle of primer.
Here's how to find more Amazon coupons to save on many other items.