Hi Bob, well, I do have an idea what it has cost me, both financially and in time, though it would be hard to tell the true cost in terms of how my single minded focus for a few years impacted my private life! However, I'm happy so no regrets!
I would say it has proved to be a very good investment but bear in mind I have owned her for 28 years and if you had told me back then what it might be worth now, I wouldn't have believed you....