Dodgy door locks

Hi all,

Hoping for some advice. My 99´Octavia has been suffering from increasingly temperamental central locking and door lock failures. It´s reaching the point that I´m concerned I won´t be able to lock or unlock the car.

I´ve never had remote locking, it´s a key-in-the-door only system and the problem seems to be age/use related.

Usual symptoms:

sometimes only the driver´s door will unlock with no further action from the central locking - doors can be opened from inside once the ignition´s on (tho not the boot!)

boot lock has failed completely- locks and unlocks only from the driver´s door

broken lock barrel on passenger side (spins round uselessly) - swapped by a friendly mechanic from the driver´s side.

I wondered if there was any mileage in raiding the scrappers for door lock motors, or in members´ experience, is it better to change the units completely? Are there any implications for the computer´s comfort package when this is done? Not very technically minded here (if you hadn´t worked that out already).

Not taking the car near the dealer as there´s no money for or point in doing an outright replacement of the system.

Your opinions please!

P