Where on Earth would you keep them? I don't remember much flat land on your property...and it's not fair to ask a large hooved animal to live on a hillside.
Donkeys are a whole different game than goats, and are not a bit like a horse. They are quite loud, too. Their behavior is such that you'd better get some lessons from someone who is experienced with donkeys and mules before you even consider the jump. Their nutritional needs are specific, also. Donkeys do INSIST upon attention, as well, so if you cannot block out time each and every day to spend with them - you will wind up with sour attitudes. Hoof care, dentistry, annual vet checks and Coggins tests...these add up quickly...