You may be surprised there have been times when the rep of a limited edition watch has been released before the gen, remember the pam cali dial? Panerai released a photo, the rep makers had it out before the real deal, only to find that Panerai changed the dial, it was at least two days before the rep was fixed and re-relieved.
The details and all the rest will come in time and education and before you know it you will sound as boring as we who obsess about a 100th of a mm
Buy the right watch and it will gain more than you think. If you had a new comex seadweller (insert a number of vintage rollys here) in the 70s, kept it in the safe, that $2-300 would be worth 10s of 1000s now