Newbie help caddy 1.6d won't start

Hi all new here had loads of caddy's over the years never had a problem with a diesel one before but this one won't start , was running well but had some work done due to these being a hobby it's been stood over a year and wouldn't start but a bit of tinkering it started but was hard to start so figured at least it's running i'll Take it to some one to have a look at once I mot'd it but now it won't start at all I tried all the obvious stuff , I'm kinda thinking it may need more experienced eyes being cast over it and here lies the problem who to use?? I can't drive it any where and who would any one recommend as a good old school diesel mechanic in Berkshire/ Heathrow area?? Most now a days seem to rely on plugging there laptop in and going from there so I'd prefer someone with experience of old vw's, thanks in advance for any advice

Take out the number 4 and number 3 glow plugs Easiest to test.
Hold with pliers
Short the nut of the plug to the battery negative, and the screw tip to the positive, if it doesn't get red hot in 7 to 15 seconds it is bad, and you need to replace all of them…

A diesel will start on one bad GP, no GP's no start.
Verify that you don't have air in the fuel (clear Line).
Verify that you have 12V to the stop solenoid at the rear of the Injection pump.

then also check the firewall fuse is still good first and that you have 12v to frame with key on both sides.. then test the GP;s after turning the car off.