2002 Volkswagen Jetta sluggish from park into reverse

My car is a wonderful 2002 Jetta wagon. 3 motnhs ago it started being "sluggish" from "park" into reverse. Nothing more then just a brief period between shifting between park and reverse, then the car would move backwards. I took it to rey Reese Moters three days ago to have it checked, to have the transmission fluid checked and they told me I needed a new transmission for $4900!
Yikes. Now what. The car is in mint condition, low miles, great interior, all the whistles and bells and now a $4900 new transmission. I've have maintained the car perfectedly. HELP