This is a bit of an oddball, but if you have $15k-20k, and don't need 4 seats, the 98/99/00 M Coupe is a GREAT car. I had one from 00-03, sold it to go racing....mistake!....lol.....

There's only a couple thousand in the US, so very unique. For two adults + luggage (or dog) it has a lot of room -- the hatch is huge. I used to carry my greyhound and luggage for weekend get aways. The S52 motor is AWESOME, probably a better street mill than the S54 (just as torquey, and more reliable). It does have the E30 suspension in the back as opposed to the better setup on the E36, but for non track driving, you'll be fine (and I enjoyed mine on track too).

Brakes are great. YOu have to watch the subframe mounts and shock towers.

If you need 4 seats, you can't go wrong with a late model E36 M3 though. Not as stylish maybe as the M Coupe (although some would debate that...lol..) but an incredibly competent car.

If I were looking for a 50-70k street car for $15k, the E36 M3 and S52 E36/8 M Coupe would be at the top of the list. M Coupe if I could live with 2 seats, E36 M3 if I needed four.