OP: Don't worry too much about your initial interview. Remember to listen more than you talk. Security will be covered in your interview. I am home based, and my IOI only wanted to see what I had for security measures. She did not comment on the effectiveness of it. I don't believe there are any security requirements in writing, although you could ask and report back. I believe visible security measures can be very effective (even fake security cameras make thugs hesitate, as do "security dogs on patrol" signs, motion sensor lights, etc.), but you need some of the real thing as well.
Your goal: the neighbors never know that you are a gun dealer.
Before your first transfer (I know it seems a distant reality now), you really need to familiarize yourself with the NICS processes, 4473 instructions, and all the goofed up, bass-ackwards rules, myths, and beliefs when it comes to dealing with WA state rules. No one at WA state Firearms Dept will be helping you, so please do as much as your own research as possible. Nice folks, but they won't interpret the law for you.
Some items I discovered by accident along the way, in no particular order:
1) The WA state RCW's were written by 3rd graders who have no grasp of English. But this is where you will find the Firearms rules:
http://apps.leg.wa.gov/rcw/default.aspx?cite=9.41&full=true2) You can watch the "training" provided by WA State DOL, but it's out of date by nearly 4 years:
http://www.dol.wa.gov/business/firearms/fatraining.html2) The WA State Pistol Transfer Application is newly revised and still sucks pond water, but it is what it is:
http://www.dol.wa.gov/business/firearms/faforms.html3) You will need to establish how each jurisdiction wants to receive PTA's, be it fax or email.
4) Get yourself set up with an online fax program, you will need it to send PTA's following pistol transfers. You have 6 hours following the transfer to act.
5) After you complete a handgun transfer and send the PTA to the relevant LEO agency, you will also need to enter the information off the PTA here:
https://secureaccess.wa.gov6) Once you get your FFL number, sign up with NICS at
http://www.nicsezcheckfbi.gov/7) Write up a business plan with policies for transfers, NICS denials, storage, re-stocking, and credit cards.
8) Read and understand the federal statutes regarding firearms law in 18 U.S.C. Chapter 44 and 27 CFR § 478
9) Sign up on FFLsOnly and learn all you can from those on the forum.
10) Read the threads here in WaGuns and research the answers so you can sort the myths from the facts.
I hope this serves you after your initial inspection and helps you conduct business accurately and safely.
_________________"To compel a man to furnish funds for the propagation of ideas he disbelieves and abhors is sinful and tyrannical." - Thomas Jefferson