It's always nice to know what happens to our old cars. I have no idea where my 3200 or 4200 are though. Unfortunately most owners are not interested in forums so the trail goes cold very easily.
I'd say around 80-90% of my customers have poured through the forums prior to taking the plunge. There are a lot of lurkers out there who don't post. Each to their own, I regularly read things on other forums but this and the other side are the only places I ever post. At the time of writing this post, there are 143 online of which 20 are members and only 4 of us have posted this morning.
Having owned a few Maseratis, I thought I'd spot my old cars more frequently, but the only ones I've seen have been my silver GS that I sold to Si Bradbury, and my Grigio Nuvolari GS popped up a year or two ago at JCT600, as for all the rest, personally owned, then ones sold through the business, I've not seen them anywhere, unless they're members on here obviously.