MG ZT wont start?

I hav an 03 MG ZT 2l Deisel. it started to take a while to start from warm. was not so bad from cold for a while. then it just would not start at all. a garage took it and did a diagnostic check. that was all and found no fault as it started ok, after that it was fine for a while now wont start at all, unwent another diagnostic check to find a fuel fault. they suggested a fuel specialist. Another garage without looking at it has said very convincingly it is a BMW engine and the fuel injectors require replacing quote was £1200 as the injectors are over £800 for the 4. Is there an option or is this the price?