we did *not* keep our _extreme_ remodel in budget. I can tell you why, and hopefully you can discern from our mistakes what to do differently!
First, our remodel was major. we bought a house that people had smoked in for 30 years. Mistake #1. I would never do that again. We had no idea how much the smoke would have seeped beyond just what we saw. So, we underbudgeted simply because we didn't realize the scope of what we would have to do. Even the contractor who came said that as they got going they might discover that things were in worse shape than they think that that would necessitate more work. I guess teh lesson here is: be really, really sure you know what you're doing and allow for the possibility that you might pull up some floor and discover a rotted subfloor or something.
Nails and other "small" materials really add up. We didn't figure on a lot of materials that we're obvious.
We got pulled into to the "well, as long as we're doing this we may as well..." which I think might be easier to do on a major, major remodel like ours, but once you get going and see the options, its hard to keep some stuff old and not upgrade along with what you're doing.
Get estimates for carpenters doing everything, even the stuff you plan on doing yourself. Doing it yourself is awesome, but with kids, its so hard. We only did about maybe 30% of what we originally planned on doing. Plus, they do such a better job (if you have good ones, that is).
I wish that i had scaled back my "wants" a bit. we ended up with granite tiles (which was actually dh's want) and now I think laminate would have been fine. I guess I'm happy with everything else, but making a priorities list is good. Like, what will we absolutely *not* compromise on and so on. Cause, you will end up having to let some things go and its nice if you already have that clear ahead of time.
Get decent materials. With kids, we were tempted to go with cheaper stuff, but then we figured we might as well get good quality that will last and take a beating and still look pretty good than getting crappy stuff that will look crappy after a minimal beating. Get good brushes for painting.
Well.. that's off the top of my head. They always joke that remodeling and building a house are 2 things that lead to major marital problems. :LOL Luckily dh and I are both pretty easy going and didnt' get all amped up about anything. Except, well, the debt we incurred later on. But, we did increase the value of our house by 80,000 having put in 40,000 so I guess that's pretty good.