That would be ideal. They build it, and then transfer it when your current house sells?
We were leaning towards new, unless the perfect existing home comes up for sale. I am tired of buying houses and having to put roofs on, windows, furnaces, water heaters, etc. It would be nice to not have to deal with anything major for a while.
Essentially, once you find a builder you like, you go into contract with them, with contingency. You work with the lender who knows youre on contingency, and get "pre-approved. At this point, your rate isnt locked, but at least you get an idea of financing.
Put your current house on the market. Now, here is where it can get tricky. Youre more than likely going to have to move twice going this route (once out of your house when it sells and into apt/rental house/whatever, then again to the new house when it closes). Some people play the game of waiting until the last minute to list their house to shorten the amount of time in a rental, but IMHO thats risky. Buyers are finicky, and no one can predict the market. We got lucky and had an offer within 48 hours of listing, but I know of others whose house sat on the market for 9 months. Then youre kinda fucked.
Once your house sells and you get all your proceeds, you keep it in the bank and figure out if youre paying down debt, what youre going to put down on the new house (which you'll need to get an idea of when you go into contract with the new lender), and wait. You'll be out of contingency at this point, get your rate locked, and financing will move forward. You dont want to make ANY changes to your credit other than paying it down. Dont charge anything, dont apply for anything, NOTHING. At this point the lender will pull again to get you out of contingency, and approve you on that pull. As you prolly know they pull the day you close to make sure nothing has changed.
Then you wait for the house to be built. In the mean time you'll meet with low voltage guy to figure out what/where/how you want any custom wiring like cat6, speakers, etc, go to the design center to pick out stuff like cabinets, interior hardware, etc. As a side note, before you do this DO YOUR RESEARCH FIRST. Have a general idea of cabinet woods, colors, etc BEFORE you go. Otherwise you'll be extremely overwhelmed with choices. My general rule of thumb is only order stuff from the design center you cant do yourself i.e. cabinets, flooring, etc. Stuff like ceiling fans, faucets, etc are usually cheaper, and best to not have on your mortgage. With that said, you should have an idea of what you want and how much it is at Home Depot etc and at least ask at the design center what THEY charge. In our instance, it saved us almost $600 ordering door hardware (handles and hinges) going through the design center. Also blinds. Do those yourself after the house is built.
Anyway hope that helps. We're in the waiting period now, foundation was poured yesterday, so framing will be next. Its a very exciting process!