Trapper, sadly, it is not quite as simple as you may make it out to be. I can certainly offer you advice as I am an 07 manufacturer & 08 importer FFL. In the past I worked as a VP for a type 10 FFL so I have a really good grasp of what you are going to face.
Firstly, you need to go to the ATF website http://www.atf.gov/firearms/index.htm
Then you need to read ALL the info there & decide on which category of FFL you want. 01,regular dealer) or 07,manufacturer)
Be CAREFUL! You said you wanted to build a couple of guns & sell them to start with but you can't do that UNLESS you are licensed as a manufacturer. ATF recently revised the rules on what is & isn't classed as manufacturing & what you intend to do is certainly classed as that.
Now, there is nothing wrong with being an 07 as you can register as an Special Occupational Taxpayer,SOT) & transfer or manufacture NFA weapons tax free. The fee for the SOT is $500 per year. However, the downside to 07 is that you should,or really must) register with the Directorate of Defense Trade Controls,DDTC) as a manufacturer & this will cost you around $2500 a year, every year. ATF is not enforcing this registration at this moment because it is a State Department regulation but I expect them to under the new administration.
So, to be an 07 Manufacturer FFL, it will cost you $2500 for the DDTC registration, $500 for the SOT & $50 for the FFL or a total of $3050 every year just for the licensing costs. Add in insurance, business licensing, rent, taxes & you have a tidy sum before you start to make a nickle.
For an 01 dealer, you have a lot less costs but you need to be in compliance with all local, State & Federal regs regarding your business. You will need business premises or live in an area that allows home based businesses.
There is much more that I could say but I don't have the time right now. I will say that you need to educate yourself about the Gun Control Act & all other firearms regulations that affect the gun trade in the USA. ATF site is a good place to start. You need a lot more info than you have shown in your posts thus far & I don't mean that in a bad way, everyone has to start somewhere but you need to learn a whole lot in not a lot of time.