How long did it take? We were told our land would be released in March, we didn't get it until July, building didn't start until October and we moved in the following March.
How much did you go over budget? We didn't. Prices were fixed with the builder.
What were the hidden/unexpected costs that you encountered? None. We made sure our site costs were included.
What would you do differently next time? Use a different builder to what we did. They were useless on communication and we had to watch every single step - ie the walls went up before the wiring was done, etc.
Anything else you want to tell me? We had a horrible experience overall, but it didn't put me off building, and has taught me a lot about making sure we document everything - the dates, times, persons name and reason for phone call, etc. We ended up with about $20K from them in cash because of their stuff ups so its worth writing all the things you're told down.