I'd be wary of this one. The advert does say that the dial is refinished, so not original.
The engraving on the movement bridge looks a little suspect.. so all-in-all, there's not a lot of evidence to say this is or was a Heuer.

My advice to you as a young collector.. as I was once the same..
Generally you get what you pay for. Long gone are the days when you can find a nice Heuer chrono for $500, even $1000.
Yes, that's a pain in the arse (or wallet), but I'd rather pay good money for a good watch, than spend $500 or $1000 on something to find out it's worth near to nothing.
Buy a good watch, and it'll hold it's value.

Stewart
Heuerville