I'm partial, but that does not mean I'm wrong. Find a good local architect.

If you can't buy existing that you want at that price, you can't build it either. New costs more than old. Custom costs more than tract.

The first most limiting factor will be lot size and location. You may have to do a tear down to get all the factors that you want.

Get an experienced local architect involved now. Otherwise your inexperience may lead you to buying a lot that really cannot really have the custom home that you want built on it. Solar direction, setbacks, utility availability, and a whole bunch of other things go into lot suitability.

IT may be possible depending on what type of house you want to build, and where in the metroplex you want to live, but I think it'll be tight.

say you pay 100k for the lot, and want to max out at 400k, that leaves 300k for the house . at 2500 sq ft you are looking at $120 a sq ft.

I shopped my highly value engineered plan to a local builder in the dfw area who does green homes and they thought they could do it turnkey for $120-140 a sq ft. Their builds are usually in the $150-$210 a sq ft range.

My plan is a rectangular shape with no bumpouts, no garage,simple roof form, etc, with inexpensive details like cheap siding. so a "normal" build would likely blow your budget.

Several years ago I had a plan to sell my large, expensive (through inflation) house and move further out from the city so I could buy a larger lot and build a small home. After much looking at property and talking with an architect and builder I had used before, I realized that there was no way I could sell my 3500 sqft house and buy a larger chunk of land and put a 2000 sqft house on it. We finally ended up buying an already built house that met all of our needs, and then some, and had over an acre of land. You will generally find better value in buying used than trying to build something. As far as I'm concerned, the American Dream of building the perfect home is over-rated. What I mean by that is people spend a lot of time, money, and energy to get things right, have a stressful and sometimes problematic experience, and still don't end up with their forever house. I understand how exciting it can be to think about building new, but there is so much housing stock already available that it often makes more sense to look for something already available, especially if you are operating on a possibly tight budget.

I'm in the DFW area and that budget will be tight. It can possibly work if you're way outside the city limits in an outer suburb, but definitely not in the city limits. If you buy in a subdivision, you're at the mercy of the builder floor plans. If you want acreage and want custom, better off going outside the city, older neighborhood that has no HOA and tear down. Your finish selections will dictate if you can build for that price.