Another vote for the Dewalt 788 :icon_thum as stated about $500 new but if it don't suit ya yer only gonna get about $300 out of it so go ahead and buy a $300 used one :gar-Bi They hold up well and are generally just used, not abused.
some things to look for :
the opening around the blade ....if it is noticeably chewed up on the either side or the back it is an indication that someone regularly forced their cuts and may have been rough on the saw . nothing wrong with this, just an indication that you might want to check other things more thoroughly.
There should not be a lot of " slop " in the upper arm from side to side with no blade installed . It will move some but shouldn't be really loose.
Tilt the table and bring it back to zero. It should move fairly smoothly and you should feel a little " bump " as it comes back square. There is a small ball bearing that helps hold it true to zero and sorta locks it .
Put a blade in it and fire it up. Turn the speed all the way down and all the way up. Should be minimal vibration even at the fast speed . Be cognizant of any " knocking " while it is running
check the deck ( table ) for flatness if it is a type 2 ( stated on the motor ) some of the type 2's were shipped with slightly scalloped decks
If it is a type 1 and $300 or less and reasonably clean ....just buy it ! Type 1's are hard to find and definitely better built :icon_thum
look for a lot of dust around the rocker switch. eventually dust gets in these and causes them to become " intermittent " switches
pretty easily cleaned but another small sign of negligence ....I have a piece of rubber glove over mine to prevent this
That's all I can think of for the moment ....hope it helps