IDK, to me the free/cheap buses end up costing a lot more down the road. But for your need it may do.
A $1500 running newer bus would be less stressful, at least to me.
If I were you I'd see if I could get it running where it is and give the dude the money if I could get it running. Then I'd drive it to a scrap yard and take the 100-1200 they will give you. Then your bus budget has nearly doubled.
Just my 2cents.