If it helps I have sold 4 cars (including a 155 and GTV) on eBay with no hassle to speak of, and for more or less the asking price each time.
The auctions can attract one or two idiots, but a well presented classified ad with 10 or so good pictures and a clear description can work to your advantage in my experience.
Similarly I have found Gumtree to be rather trying (folk you would try to avoid in the street, offering derisory amounts)
And Pistonheads seems to attract car bores who only wish to sneer at your car because they already have one that is so much better....
Best of luck, not really the best of time to be selling unfortunately.
Sprint - 33 - Sprint - 33 - 155 - GTV - GTV - 156 - GT ...gone German for now though.