if you get a mint Rolex with all the paper work, something that MSRP's for $6k - $7k that you get for $5k, you will not have paid too much because you'll always be able to recoup most of your investment easily if you decide to sell it.
a lot of other watches do not retain resale as readily, or at least take more work to sell. Rolex has such broad appeal in North America that it's a safe bet. As is Omega.
Lower end watches like Tissot, Movado etc. can be bought at outlets or department stores on deep discounts and have little resale potential.
Higher end, more obscure stuff like Glashutte, Zenith, etc. have a more limited market (Serious watch douches) and are a bit tougher to flip than a Rolex.
Hamilton is a good entry swiss watch, however, for a starter auto i would recommend Oris. They are the official BMW F1 watch and you can pick them up off ebay, WUS or timezone for great prices, fully depreciated. I made money on my first Oris and wouldnt lose on the Oris that i still have.
however, even though the quality is there with Oris the wrist-presence is not up to Omega / Rolex / Panerai