I would recommend establishing a relationship with the authorities as early as possible. Go down to your county DMV (or equivalent) with The Book and snapshots of whatever gear you've accumulated and tell the inspector what you're up to. Get to know him/her/them on a first-hand basis. If he finds your project interesting (why wouldn't he?), invite him over for a look-see.
The purpose of this isn't just to get all pal-like with The Man (although that doesn't hurt). The first reason for this is to get information from him *before* you put hundreds of hours into something in a way that doesn't fit with his program.
The second reason is to give him an opportunity to learn from you. Let's face it...this guy reads 2,000 VIN's and speedo's a year. Maybe listens to as many horns honk and admires 4,000 turn signals blinking. He takes a check, punches a computer, and signs form ST-4032-b-sub-j9/revised:9.505/canary in quadruplicate. Has he *ever* processed a homebuilt car? If so, does he do more than 2 or 3 a year? Maybe...but probably not.
So...your job is to present yourself as an intelligent, motivated builder-citizen. Make it clear that you are there to learn what you need to do to register the car you are going to build...not *if* you can register it, but *how* you are going to do it.
Do as much research as you can before your first contact. Don't pass yourself off as a know-it-all or arrogant, but know your stuff. If you run into an issue that you both don't know the answer to, admit your ignorance and offer to do some research and then go do it. Follow up with him. *Never* bluff your knowledge. Treat The Man as your partner, and make it clear that you are going to work *with* him, and that you expect him to do the same with you. Let him know you appreciate the time he spends with you. Look him in the eye when you shake his hand at the start and end of your visit.
If you have some literature on your vehicle, offer to give him copies for his interest. If he seems interested in what you're doing, loan him The Book for a week, and follow up and listen to his opinions.
If you run into a real arse that has "I hate kit cars" tattooed on his forehead, find someone else. Call before going downtown and see who's working that day. Make sure you have a reason to talk with Joe instead of Lucifer, such as those pictures you promised to bring him the other day.
The more opportunity you have to learn from him, educate him, and involve him in your project, the greater the expectation that by the time the paperwork hits the desk, all issues will already be understood and resolved.
I base these assertions my experiences in my other [Fatherless Child] sport. I fly ultralight airplanes for fun and anti-profit. I've meet a variety of aviation professionals, bureaucrats, and experts who have an extremely thin understanding of my tiny little niche of the aviation industry.
I've flown 200 miles to be told that I can't buy gas at a "real" airport because I don't have a "real" airplane or a "real" license. I could have gotten belligerent, yelled about regulations, begged, skulked off, landed at the truck stop, or all kinds of other unsavory things. Instead, I scratched my head and said, "Gosh, I'm sorry...my flight briefer didn't mention any NOTAM's about ultralight restrictions here Westfield when I filed my flight plan this morning in Kentucky."
By letting him know that I know my stuff (using his lingo, referencing the authorities and regulations) and I'm not some kite kiddie (Kentucky was a two hour drive from there) he quickly decided that he might as well sell me my five gallons of gas and let me move along so he could go back to his bread and butter...selling 200 gallons of jet fuel per pop. We both got what we wanted, and neither of us left with any incentive to give the other any grief. I can't wait to return there!
-dave
ps. This is my first post to LocostUSA. I've read The Book several times, have been reading the net's wisdom for a month, and committed to build a garage this spring. (And yes, I've already had a chat with a clerk and inspector at the county clerk!) I'd say I'm 75% likely to start a build...we'll see. I sure like what I'm seeing and see it as a great way to learn a raft of new skills. Thanks for all the posts!
Ha! I'm glad that I'm not the only one that gets only bits and pieces. 
