It seems amazing to me that your mechanic is expecting you to get the vehicle started. If you can't find a competent mechanic, can you rent a storage unit or garage to keep the Rover in until you can look at it? This thing is 20+ years old, there are bound to be things that need sorting. I second installing a new Crankshaft Position Sensor. The CPS can fail completely or intermittently and not throw any fault codes.