Value depends on many many things.Colour,mileage,history,spec,etc etc.
Condition of roof is all important.
It's the worst time of year to sell one but best time to buy.
Prices vary,the 3.5 seems to sell better than the mk3 though as the standard mk3 convertible is a vbit basic and bland,the 3.5 is a little better finished.
Could be anything from 100 to a 1,000 but only the nicer one's tend to actually sell ,mostly it's the lower end if that figure.
For example :-
https://www.gumtree.com/p/volkswagen/vw-golf-cabriolet-green-2l-51-plate-no-mot/1200167774Me personally would'nt buy a MK3 convertible unless i was just loooking for a cheap soft top.There are loads about.I would buy a 3.5 though but would be prepared to pay a little more for right car.
100k miles is on the higher side for a convertible although not excessive.They tend to be low mileage due to their seasonal use.
A good choice for a soft top though,cheap to maintain,insure etc.
Good luck.
