Fabia HTP electrics problem

Greetings all ... I've bought another skoda, my 4th!

Can I ask for some thoughts on the following please;

1) Passenger airbag off, light on dashboard goes out yet warning light in the clocks stays on.

2) Door lock switch on centre console does nothing

3) Stereo sometimes just doesn't work

4) Revs fluctuate between 500-800rpm at tick over.

5) £55 of fuel put in but gauge only showed half full, after 130 miles the reserve light is on.

Taken back to vendor garage who have 'a man' who looks at electrics ... He had it fo 5 hours on Friday, and its no fixed yet . Apparently an airbag module is required?

What I'm asking is, is there a serious underlying problem here, or just a few gremlins?

It's a really nice 2007 (07) plate Fabia 2 HTP and 54k miles, in great condition.

Thanks

Edited 17 February, 201313 yr by b1ackb1rd