Hi to you all as im new to the forum

I was hoping you may be able to help....
Whilst at work the other day i began chatting to a retired chap who mentioned he may be selling his Mk2 gti 16v.
I am finding it hard to put a value on the car as its an earlier car with a few rare features.
A little about the car.....Its a early 1987 D GTI 16V in Monza Blue with a fatory fitted BBS bodykit and wheels.
It has sunroof, electric windows, central locking but no power steering.
Its not mint as its been stood for quite some time and would require part resto.
This aside, the chap has owned it since new, it has only 70k genuine miles with all history, tax discs & mots.
Its very straight with original dealer supplying plates and all window etchings match.
Wax oiled from new so doesnt suffer from any of the usual mk2 rust probs although does seenm to be bubbling under the 80s marmite kit.
Plan would be a long term project possibly returning to a small bumper gti although im still undecided on this.
Please let me know your thoughts on what you think a fair valuation would be for this in its current cond.
Many thanks,
Ben.