VRs central locking

my 2002 VRs has developed a weird problem ,first of all the passenger window wouldn't shut ,then the central locking stopped working and then it wouldn't start ,o collected by garage and £450 later they tell me they've investigated and re set all the computers and remade a lot of earths and it's now OK - two weeks later the drivers door lock doesn't work with the fob (does with the key) and the electric mirror only operates on the passenger side,the heated mirror doesn't work on the drivers side either ,any ideas ? it has been suggested that there is a unit in the door itself that may be at fault - has any one experienced similair problems ?any solutions