The first thing you must do is not to buy any pocket watches for the first six months,What you must do is view as many auctions under vintage pocket watches or antique pocket watches and look at all the prices of all the brands to get an idea on how much you want to spend and the quality of pocket watch you want,You will find that a very few Swiss brands are very expensive,For example Patek Phillip and Constatin Vacheron are top money and then the next expensive watches are made of solid gold 14k to18k and Platinum and are Railroad Grade pocket watches these watches are 17jewels or higher and adjusted to temperature and five to eight positions and are size 16 to 18, Most are size 16. A collection of railroad road watches will be expensive about $300-$4,000 each depending on the material the pocket watch is made of.I.E.solid gold or gold filled and the rarity of the watch.How many were made,if it was made for a private jeweler and the year it was made.Most Swiss brands are cheaper than American brands.The most expensive brands are Howard,Hamilton,Illinios,Waltham and Elgin in this order.The Walthams and Elgins are about the same price.A nice way to start a collection is to look at the size 12 pocket watches these are the most affordable for your money,Even the smaller pocket watches size 6,0 and 3/0 are more expensive than size 12.But the most important thing to do is watch the auctions and see what the pocket watches are going for and then pick out the type of pocket watch you want,for example a hunter case, Thats a watch with a cover and a button you press to open the lid to see the time or an open face were you see the time always.Just take your time and make notes and if you have any questions you can go to this web site for free nawcc.org and if you become a collector then you join the NAWCC to help preserve the past and future of horology.Good Luck.