Congratulations!!!
In regards to locking the rates, I've seen lenders offer anywhere from 30 to 120 day locks. Sometimes a premium is required for the longer locks. That being said, if 6 months is the "true" construction time, then you will have slightly less risk. I might add most homes are built in 3-4 months unless you experience abnormal/bad weather conditions.
Also, keep in mind, with a custom home there are different ways to setup your financing. One is to simply sign a contract with a builder that is similar to buying a house that is for sale on the market. In that scenario, the builder assumes all the risk for procuring a construction loan, etc. All you do is qualify, throw up the earnest money and pick your colors, etc then go to closing and take possession.
Another way is for the OWNER to procure a construction loan to hire contractors and purchase materials and towards the end of the process, it converts into a normal home loan.
Which way do you plan to proceed?
It is only the poor who pay cash, and that not from virtue, but because they are refused credit. - Anatole France
FICO Scores (1/6/13): EX 642 and TU 670
Starting Score: 529
