RTD The price really depends on how much you want one. The market is a little flat at the moment so I expect there will be fewer bikes available while owners hold on. A good clean bike will probably range between £20K - £30K. Given their age I think fully original, low miles, perfect bikes are few and far bewteen so you need a bit of luck.
For example, I found my bike by accident while looking for a part for my SP3; I bought my SP4 with about 1500 miles on it from new, completely original. I have put a further 6000 miles on it so far, dropped it at stand still, given it regular fluid and belt services, and replaced all of the bits that fail with age (fuel lines, filters, pumps, hoses, brake lines, etc.); I don’t expect to get what I paid for if I were to sell it. Plus the amount of money spent on spare parts just in case doesn’t bear thinking about! 😆
Hmmm… not sure what conclusion can be drawn from this ramble other than set a limit to what you will pay and accept that it will cost you more, especially if you want to return it to fully original. They might start to become ‘investments’ for the next generation in the same way all old, rare things might become more valuable over time, but probably not in my lifetime. Personally I don’t understand the view that these bikes (or any bike of this era atm) are ‘investments’ as they cost just to keep running and they are very satisfying to ride so it is impossible not to do so.
Oh, and the Ducati team in Bolgna are really helpful in verifying numbers, etc. but they will only provide the service if you are the owner or an official dealer. At least that used to be the case.
Cheers, Kev.