This is not a real argument because it depends on a multitude of factors : wear condition, documents of the watch, brand of the watch, model of the watch , etc etc.

In most case scenarios, specifically regarding older models, there is a lot of market for them out there and considering the niche of the market (luxury) there are people that are willing to pay a higher price in order to get a sough after item such the items that OP seems to be aiming for.

Again, this is an investment so it pays off in the mid-long term.