I usually cut down 1 tree for 100.00 my minimum unless climbing and topping is involved. I am licenced and insured and have never had a boo-boo in 25 years..
I think $800 is a bit steep, but, then again, you will pay a lot for that experienced arborist. They are a very specialized trade. We were quoted for about $500 just to cut down a dead pine, so trimming etc. Would probably be more.