So you’ve come in for some fairly harsh responses here, with justification. Many members of this forum have years and years of learning behind them, and they generously offer it here to others who share the hobby. There’s a pretty clear condition with this, and that condition is that they are sharing their knowledge with collectors, not aspiring dealers. Why would they do that? Collectors don’t want to help someone who’s purpose is to increase the scarcity of reasonably priced watches.
Here’s something that might be useful for you: go onto YouTube and watch Simon Freese’s series on turning £100 into a Rolex. Essentially he takes you on his journey of buying and selling watches on eBay making a profit each time until he’s able to purchase a Rolex with his profits. But here’s the thing, he has to add value to each watch in order to make a profit and he’s able to do that by repairing and restoring watches because, guess what, he’s been doing that for over 20 years.
If you’re going to flip watches how are you going to add value? Buy low, sell high? OK, where are you going to buy watches at below the market price, even if you know what you’re looking for?
It’s not as easy as you might think, but I wish you well. Everyone’s entitled to make a bit of money, and everyone entitled to be offended when someone asks them to download their patiently acquired knowledge.