After reading the posts I'm still not sure if I have a handle on cost differences between adding a detached or attached garage/shop. I haven't nailed down what I'm going to do yet. I currently have small shop (inadequate) in the back of an oversized two car attached garage. The garage is on the left side of the house. I'm considering extending out toward the street with two doors again facing the street. I'm also considering extending out for a three car with right side facing doors. A third consideration is adding a single car garage with shop to the right side of the house. The first two options allow me to turn the old space into half shop half game room. I'd love to get a ball park figure on all three to see the impact on pricing. In any case I will be doing the electrical and the interiors. I hope I have'nt jumped off topic here.

In the end, there are largely two types of people who comment on these threads. Those who are building houses and those who have built houses. While I admit certain people who have built houses in the past are a bit jaded, I think you need to realize that experience does count for something. I advise those who are starting the process to not so quickly discount the advice of those who have been through the process. I have built two houses in the past and was solidly into building the third when I decided not to do it. I had firm pricing to get it done and was pretty confident that I had an initial cost laid out, and my house came back more significantly higher than the OP's. Construction labor in my area is only 8% higher than Texas, but my house came back at almost 30% higher, and this price didn't include flooring, bathroom fixtures or cabinets. I do realize that it is possible for this to happen but become concerned that the OP is focusing on the wrong items. I feel my concern was validated when he posted the specs of his custom build. A 14 SEER AC in Texas is a bit silly. In fact, it doesn't even meet the currently enacted future minimums. The marginal cost of 16 or 17 SEER is reasonable in North Texas, which has something like 3,000 cooling degree days. My experience tells me that this isn't the only questionable thing going on here. Someone who is willing to cut that corner is probably going to cut others. The question isn't whether or not you can build a house in North Texas for $120 per square - the question is should you build a house in North Texas for $120 per square. In the end, labor and overhead are only so much of the build. Please don't feel the need to answer that question for me. I don't need, or even care, to know. However, you might consider listening to some of the people who have completed their build, because it is tends to be a bit of a humbling experience.

Sorry this is not a question that can be answered it depends on so many things and you should know the answer IMO before you think you can give estimates on anything. Remodelling often costs more than new build and estimates are not written in stone but you still need the skills to be a ble to come close IMO.

Once you have more info, you'll get some excellent advice here. Good luck. As I said, we built our retirement home a few years ago and moved in 2 1/2 years ago. I made it a point to post everything here and listened to all comments, even those that sounded snarky because there was some good advice hidden in them. My house lives very well. Might I suggest you start by reading an excellent book? The Not So Big House by Sarah Susanka. An excellent and easy read that will truly have you thinking. I also suggest you look into what some things might be needed for as you age. Just a few examples from my build to give you an example: 1. We are in a flood zone so had to raise the house 3' so that means steps. However I designed the house with the ability to put in a ramp in our garage, just in case one of us ever needs a wheelchair or walker. 2. All hallways were supposed to be 42" wide. As it turns out, the builder screwed up and the hallway to the master is only 39" wide with molding on. 3. We put our laundry right next to the bedroom since most laundry is generated from the bedroom. Makes it easy to carry back and forth. 4. While we did put our toilet in a "closet", I had it designed so if one of us ever needed more room to maneuver, those walls could easily come down. 5. There is blocking in the walls around all toilets and in the master shower in case we need grab bars. 6. My hand held shower is on a slide bar that is also a grab bar. 7. I have a free standing tub in the master across from the shower. If we ever need the extra space because of a handicap, it's easy to remove the tub to give easier access to the shower. 8. We are on a small infill city lot so had to go up. My studio is upstairs as is the guest bedroom/exercise room and the guest bathroom. Because of this, we put in an elevator. It's great for hauling boxes and suitcases up now, and it makes a great storage closet too for now. 9. All door knobs are not knobs but handles. 10. In the kitchen, all lower cabinets are drawers with the exception of my prep sink cabinet. 11. There are no floor transitions. While we do have tile in our mudroom/friends' entry and in the bathrooms, it's all on the same plane as our wood floors. 12. The shower is curbless in the master. There's more but you can start to get the idea. I learned this lesson when I watched my very active Mom develop Parkinson's disease starting at age 72. This was a woman who went to the gym 5x a week and on the days she didn't, she walked on her treadmill or walked around her neighborhood. Near the end even the one step into the house was like climbing Mt. Everest. Luckily because she too had planned ahead, she was able to stay in her beloved house until the last 6 months of her life.