It's really hard, but try to look at the place objectively.. don't say "yay it's great!" just because you can have your horses at home - although it's very tempting to do regardless ;)
One other thing I'd like to point out - and I know it seems silly, but it might wear on you after a while - is that when your horses are living at home with you, there's no escaping them. Vacations become harder because you have to find someone that you trust to care for the horses while you're gone. You can't just go away for the weekend - at least, it becomes harder - it takes planning, you can't just go on a whim. Remember horses do better when they're fed on a regular schedule; if you feed at 8 am (or whenever) then that feeding time shouldn't vary much.
Another thing to consider - how far is this place from the vet? This is a thing to consider for call-outs.. it adds up :) (especially when you have to do call-outs for little things like vaccinations if you're not comfortable giving the injections yourself)
I'm sorry for the novel, I just know that if I was looking at a place like this I would get starry-eyed and just focus on the positives and ignore the stuff I'm not very happy with just because I'm star-struck with the place, and I'd need someone to keep me back in reality with things like these :)
Best of luck!! Take lots of pictures!! I want to see!