You're very wise, BeeEmm, to be cautious.
May I give you a piece of advice? Please forgive me if it's obvious. I don't want to offend you or anyone else, but I think it's worth saying, anyway. It's this. Apart from Rolex* and unless you're rich, never buy a new watch from a shop, unless it's very heavily discounted.
Please remember that the mark-up on most new watches is 60%+, that most watches under, say, £2 or 3K have a large number of parts made in China & surrounding countries, even though the dials say 'Swiss', and that much of the watch world is as close to dishonest as it can be without breaking the law.
Some answers to this problem are to buy second-hand from the watch equivalents of the Z4-forum, from decent online dealers and from shops that have used stock at fair prices, remembering all the while that there are very few good investments in watches..
*As you no doubt know, modern, new-production Rolex value (and, therefore, second-hand value) depends on the box & papers that are available only from authorised dealers.