Just one tip- KEEP GOOD RECORDS IN A BOUND BOOK. Log everything in and out faithfully and accurately, don't wait until tomorrow. And don't do trading for a profit- if you want to trade and buy/sell to get the best collection, fine...but don't do anything that would cause you to be judged to be "engaged in the business."
Oh, yeah....keep some copies in the car and in your wallet...the best finds are surprises!
