Your best bet will be to look up local area barns on the internet and see what they charge. Each area is so different. Where I am now, in rural Wisconsin, I pay $300 for a private pasture with hay free access, 2x daily grain, turn out 12 hrs, blanketing/fly mask, 1 indoor arena, 2 outdoor arenas, a cross country course, trails, closed tack room with humidity control, bathroom, lounge and the barn owner will spray them off in the summer if they look hot.
In Ohio suburbs where I was before here we paid $425 for sand paddock turnout with 8 - 10 other horses, grain 2x day, hay 3 times day and that's it. It really will depend on your region.