That sounds like a decent price Akshay. If you use the 'completed items' search on eBay you can see what others have sold for - here in the UK they seem to go for £130-£150 used.
I couldn't comment on the quality having never tried one. I used to have a Boss ME-50. I was a guitar noob when I owned it so I probably didn't use it right, but it was built like a tank!
As far as checking for things - make sure it works
I think especially with the Boss products and their build quality there's not a lot to go wrong. Just whack on a patch, make sure it makes noise, check the cables don't crackle, expression pedal works cleanly etc..
I always end up back with Line6 - don't ask me why, my Toneport is a nightmare most of the time. They just announced a new HD version of the POD desktop unit at MusikMesse which I reckon will be my next multi-fx. Either that or the POD HD500.