The best way to do this is wait for a Tap In promo and get a haul of extra Premium balls and Apparel packs at the same time and use accumulated video or survey credits instead of cash if you have them.
The only reason I got a Plus membership was to be able to get through the L90s equipment purchases within a year. You have to keep the daily play streak going and play heavily to make that work. When the year is up, I don't see any reason to renew.