Get a written list of just what was serviced and why, especially the 500C/M body and the backs. These Hasselblads are now quite old and ideosyncratic problems and lack of knowledge of the operations specific to Hasselblad often lead to the need for repairs. That and how they have been treated over many years and thousands images. Just because it is a Hasselblad doesn't mean it is forever free of problems. I would pay particular attention to the service of the Hassie 500 and the film backs.
The 45° prism finder is always useful. But it needs to be checked for any fungus (uncommon, but I have seen two examples I instantly rejected based on the presence of fungus).
The 50 and 80mm lenses are universally favoured go-to primes and millions of them are out there, some better than others, irrespective of being the C or CF model. You need to be absolutely sure of condition of lenses and things you don't want before aspiring to get a target price. The 250CF lens could, for all intents and purposes, be dented, bruised, scratched...what else? And still quite serviceable. Well presented specimens can fetch well over $500.
As for your last comment:
"Is this a very good deal? An okay deal? Or a bad deal?"
I would say, a bit of all three, and buyer beware.