A Type 01 FFL is a dealer's license. The Feds are pretty much limiting it to only people who have a real gun shop. You have to provide a business tax ID number, and your premises have to be zoned for it. Obviously, it allows you to buy any type of firearm (except restricted stuff like Class III weapons) and sell them.
A Type 03 FFL is a collector's license. This is what I have. It is for collectors of curios & relics. It allows collectors to engage in interstate commerce. I can buy C&R firearms anywhere in the US and have them delivered to my door without having to go through a dealer or fill out paperwork or go through background checks. It, however, does not affect the way I buy modern firearms. If I wanted a brand-new firearm, I would have to do it just like everyone else. The BATF maintains a list of C&R firearms on their website.