If you’re checking a Rolex before getting a quote in San Diego, the reference...

https://cashsexcellentblogs.rivetgarden.com/posts/is-it-normal-for-a-rolex-buyer-to-inspect-between-the-lugs

If you’re checking a Rolex before getting a quote in San Diego, the reference number is typically engraved between the lugs at 12 o’clock, under the bracelet. Don’t force the bracelet off just to find it; a watchmaker can check safely