Is there an online service giving you which cashback provider gives the best ratio, or we have to check manually?
Topcash Back, Coupert, Rakuten
Rakuten is the best
Capital One Spark credit card. 2% cash back.
I only do wholesale so others don’t work.
Rakuten and TCB
Airtime rewards, curve, capital on tap, cashback sites are the 4x stack you want.