: I have a 510 501 pre - TAG. I have been doing some research to try
: and come up with a value and have a range but would like some
: more input please. It is in near mint condition. Keeps perfect
: time, everything works. Looks to be all original. Just a couple
: scratches that can barely be seen and some wear on the black
: finish on the band. Any values AND history would be greatly
: appreciated! Im including a picture. (If the link works...lol)
: Sue

Hello there Sue.
These have become scarcer recently and as usual value depends a lot upon the actual status.
The 510.501 is one of the Lemania 5100 powered Heuers and one of the last 'true' Heuers. It was in catalogues from 1983 to 1986 and later it was modified (different movement) and became TAG Heuer 510.501/12 - one of the few to make the transition. Yours is a very nice example of the day-date version, which is the rarer in the black PVD - the other being date only.

It is a very, very sturdy chronograph, perfect for everyday wear. I have one and it was my first 'vintage' (well, in the sense of pre-TAG) Heuer.

If the conditions of yours are indeed mint - hard to say from the single picture but it looks a bit worn on edges, so more VG than mint in my opinion - the value has indeed increased, helped and abetted by the general appreciation of Heuers lately.
Assuming mechanical conditions work spot on, on its original bracelet the value is higher than 1000 EUR on a private sale, let's say between 1000 and 1500 - depending on the overall conditions of the PVD, whether or not box are included etc.

Hope this helps.
Cheers,
Fabrizio