Just because you asked about pasture prep that is what I talk reply about. Right off, clear all the junk, run a large powerful magnet over and over and over and keep going until you don't have any nails, screws and all pieces of metal up. Cut down all weeds and pick up all glass, and plastic and rocks. Catch, kill, remove some how the gophers the net work of holes make the ground weak and the horse can and will fall through. Have someone till up and smooth, grade the area, put down footing. A 17 hh horse is going to make a mess of a small area really quickly, so small gravel/sand is needed, as well as a properly graded to help drain water. Keep walking with a magnet and picking up stuff, it will appear out of no where even when you think you have it all.
Make a three sided shelter expect to spend at least $500 for a cheap chip board (10 by 10) to $6000 for wood siding and all the fancy bits like kick boards, siding, shingles, and more (at least 10 by 20 for two equines). Even for an acre of land expect a couple of thousand in fencing. Do it right the first time, it's more expensive to fix monthly because you didn't want to spend the money to cement in the posts, or when electric fence insulators pop off or ground out. Make sure the fence is tall enough with enough strands, just because one strand or board can hold the horse in doesn't been it is the best or safest idea. A donkey will get out if you don't, they also can't have as much to eat, how can you going to make sure they get the right amount of hay without a obese donkey from eating the drafts hay? Donkey can't be on tons of pasture.
Look up a list of poisonous plants for your area, till, smooth, put in drains, fence in grazing area, a feed store or country store probably will carry a grass mix for a horse pasture made for your area, expect at least a few hundred in grass seed alone, lime and fertilizer will probably be needed if only weeds are growing now. It needs at least a year before the grazing is ready and strong root system, before grazing it has to watered, and mowed to grow strong, along with other care.
This is just the tip of the iceberg but a start, highly recommend do it right the first time, don't pay twice. Expect at least $5000 to well over $10000 in shelter, fencing, another shed for hay (not a years worth either just a month at most), hay, footing, grass seed, grass management, manure management (what's his plan for 50 to 60 pounds of it a day?), grazing management, fence repairs, labor fees, and all the little things, like stock tanks, heaters, hoses, buckets, feeders, wheel borrow, shovels, pitch forks, feed, and storage for everything (saddle racks etc).
Last edited by Cruiser; 08-09-2012 at 04:25 PM.