Ford Transit 2.0 Diesel Euro 3 Bj 2003

Hey people wanted to have questions about a transit year 2003 the TÜV is now due so it is even run out in December 2015 so I have to drive to the Tüv in the next 2-3 weeks now told me auto mechanics that possibly repairs of up to 1000Euro could be pending then it would still be worth keeping the car. My question to you the car has Euro 3 and a few kilometers is also not bad the engine runs well however are some things to do rust underbody, brakes, ra dhaus etc. it is worth to invest in the transit still 1000 Euro or rather sell. I am grateful for every tip or advice.