i'm not sure what side of the world you are in but generally 86-92 non turbos aren't too bad on price, i think add maybe $1 or $2k on the turbo's.. for the mk4 93-98 usually they are between $12-20k depending on what options, manual/auto, turbo non turbo, sport roof etc
have a look at your local auction site or trade paper and just have a look to see whats around