You are asking for a lot in an 18' boat. Especially finding one in your price range. I would look at a Compac 16 or 19. Not performance orientated boats. They actually probably fall in the category of slow. Another slow one to consider is the West Wight Potter, they have a huge following out west and should be readily availlably. They make both a 15 and 19.
The Oday that was mentioned are good solid boats and they should all fall in your price range. There are a couple here in my neck of the woods (sw Missouri) that are for sale in the $2000 range. The capri 18 and the precision 18 are also nice boat that can be found in that price range.
always in decline-never hitting bottom