If you want to pin down costs, you have to get estimates.

For most phases of your build, you might want to have the subs provide the materials and labour. Indeed, that's the standard for a number of trades, including roofing, trim, cabinetry, siding and aluminum work, plumbing, painting, electrical, stairs and rails, security and central vacs, HVAC, drywall and taping and concrete work.

Just a tip on framing lumber prices. In my area, wholesale lumber yards beat out the retail chains hands down. (Except for PT )

I second what Worthy said.
Stay away from the big box stores. You're paying them to be the middle man. Search for subs on your own and get multiple bids. You'll need to have many many copies of your plans to hand out for each bid. Don't count on getting the plans back.
You'll find the bids can vary greatly. The three roof bids we got (18,500, 24,000 and 38,500) for the same shingle. Our lumber was from a wholesale lumber yard. I wanted to be able to buy my own plumbing fixtures, so our plumbing package doesn't include them. The other plumber that bid the job insisted I buy thru him. I was against that so he was history.

We did hire a manager to over see the project. By doing so, we are able to use his contacts and get his contractor prices. Our savings probably paid for his fee. I paid all subs myself. I got the release of liens from subs too.

Cabinetry, you can probably have custom cabs built for what you would pay at HD or Lowes.

I can tell you that having never OB before, we never would have gotten this far w/o the manager. Our next step is insulation, then drywall. We can pretty much take it from here but still want to keep him on for guidance, just in case....

Good luck. It's a huge undertaking.

You can find independent estimators that will do take-off for you. We paid someone to due this so we could have an apples to apples comparison of the lumber package and not just each stores take on what we would need. He also provided a color coded framing design plan that we were able to provide to framers so that they know what lumber was bought for what, therefore minimizing waste. If you can't find someone in your area I can provide the info for my guy. If you have the plans in electronic form I'm sure he could do it now problem and then mail you the framing plan.

As far as I know, HD and Lowes don't do lumber takeoffs. You give them a materials list and they bid it. But, it's been three years since I sold my construction company, so things might have changed.

Last time I checked (earlier this year) the HD in my area would do a lumber takeoff for $300, and then use that as a credit if you purchased from them. My local lumber yard beat their prices anyway, so I didn't bother.
You will find out quickly that HD and Lowe's will not be able to fill in many of the blanks on your cost sheet. Like mentioned above, actual subs are your best source of info. Almost everyone I talked to regularly bids from plans. On top of that, one sub can give you references to five other quality subs in other trades. I have landed several good ones this way. My experience is the same as jgirl, my lowest bid was half of the highest in some cases.
I think it's great to have some builder bids to compare with doing as an OB.
The internet is a good resource to learn the right way to build, but when it comes time to do it you have to get out and beat the bushes locally.
Did I mention the importance of talking to subs?

Great thoughts! Just FYI, I would never use HD or Lowes for the materials purchase-just for a take off comparison to help with base cost analysis.
Comfortdog

rachelh........How do you go about finding estimators? If you are still willing to give our the info for yours that would be great!
comfortdog

I don't know where you'd go to look for one. We are owner building through a service so they gave us his info.
Dale Strickland with Trophy Estimates
dale@trophyestimates.com
His phone number is 281-893-3444
I really don't remember what the charge was. He charges by the square foot.
Good luck!

Rachwlh= Thanks for the estimator info. Do you mind me asking what service you are using? I have met with Ubuildit and talked quite a bit with a COBS rep. I just recently found out that a Buildmax rep lives very close by me. I hope to talk with him soon, too. I have met with 6 builders and I still have other options I haven't explored. We love our "paperhouse" as I call it, but know that the budget is going to be really tight to pull it off and not feel so pinched in the process. It doesn't help that the market has cooled and the value of our home has dropped. We could still sell it for more than we paid 5 years ago, but not by much.
comfortdog

I just wanted to add that the reason that we chose to go this route is because my husband is doing the mechanical work himself, plumbing, electrical and A/C. So while there is a fee it was covered by our savings on plumbing alone. My husband also likes the control he has over the quality of the build. He loves going to production homes now and being amazed at what he calls "crap." So in the end it might take a bit longer but he has a huge sense of pride in our home.

I would never use HD or Lowes for the materials purchase

Don't write off the big-box stores on everything. Using my contactor account, RONA (Canada only) supplied upscale plumbing fixtures on a recent home for less than speciality wholesalers wanted; ditto on locks.

I got lumber take-offs from local yards. For everything else I spent long hours in HomeDepot and Lowes. I made my own detailed list based on Indymacs Construction budget and got prices and specifics on most items. Some I just used a general price (exmp - flooring $5sqft) that I knew I could do the job in. I also do not know specifically what items I want, such as doors. I picked something that would work and used those numbers, knowing I will choose something close to that level of finish.

I do not plan on buying everything or even much from them, but they will always be there and it is a good base price. If I can find items cheaper, great if not I know how much it will cost. I am doing most of it myself, so when I see what I want at a good price, I pick it up.