We get a ton of rain here, so I'm a big fan of blankets. Rain=Mud + Rolling Horse=Muddy Horse! I hate grooming through mud and I hate tacking up over mud remnants too!
Anything called a "stable blanket" or "water resistant" is not water PROOF and I won't buy it. I guess if your barn changes your horse's blanket before and after turnout every day, it might be nice to have a separate "stable blanket" and "turnout blanket."
2 heavy weight blankets with neck cover (Waterproof/Breathable) for winter.
1 medium weight blanket (Waterproof/Breathable) for late fall/early spring.
2 Sheets (Waterproof/Breathable) for fall and spring
2 Fleece coolers for cooling out or shows (if we ever show)
1 Irish Knit sheet because it was by Amigo and like $9 new.
2 Fly Sheets - haven't decided yet if I'll use them this summer.
I usually buy 2 of each type so that I can be sure to have one available to use if one is at the cleaners.
I've become a real "clothes horse" har har har I used to just skip past the blanket pages in catalogs....now I ogle over them for hours!