First think about what goes into making the final cost of any house. Try to understand those for your area.
Paperwork to include engineering, surveys, drawings, permits, etc, etc, the stuff that adds nothing to the sticks / bricks as built but may / may not be required for the best built house. In some areas this alone can be big dollars, maybe talking as much as $25 - 50K.
Land - A major part of the cost and an area where you can have some control if you can purchase it yourself cash.
Actual materials used during construction - You only get what you pay for or can acquire by some means. Can have a great debate what might be a typical percentage of the final cost. This is usually less than most folks think as a percentage of the total cost.
Labor - This is always marked up by an amount over what is actually paid out. Different designs / housing styles will require more labor for the same square footage.
Profit - Not all builders will make the same profit on the same house. The methods / management / techniques are key. One thing in particular is builders who use many subs that they do not control tend to make less profit. The better builders will always have total control over each trade, probably including the ability to do most tasks themselves. Those subs they do use will probably be captive. This one area might be the one where a builder can cut some slack if he has to really bid low.
Other - All the incidentals like interest to carry the job, equipment purchase / replacement and anything that did not fit into another category.
Also understand any builder really wants to keep building the same box over and over again. They make the mistakes once, hopefully refine the process, the crews become used to certain tasks, procedures, methods. The houses may look different, they are the same basic box. They never want to build radically different designs, they want to keep it almost like an assembly line type mentality. The materials list is basically the same, the best builders will have pretty much zero scrap, they can bulk purchase for many houses. All the rest is a bit of eyewash. Each thing does have a price but it may not matter all that much.
Anything that is toward "Custom" or radically changes the basic box will probably increase the final costs. The nitpicking details don't count all that much.
House location and number of suppliers is another cost factor that will make the same house costs different in various areas. The more in the boonies, usually the higher some costs but that may get cancelled out by far less regulation. Lots of variables to play with.
If you can purchase the land for cash at the right price that is one way to affect the total cost.
There are tons of experts on this subject. In theory the bigger builders should have the lower costs, not always true. You might have a raging debate what the best builders will look like. From my experience, something like a very well organized mom / pop type builder who has many years of experience, is very well connected to the suppliers is the best type builder. Not only from a cost point of view, they can deliver the most quality.
I am also looking to build a house. Not in a huge hurry. Probably will do the bulk of all the work myself. Been waiting for the depression to really bite bad, wanting land prices to fall even more. Finally starting to happen.
In SE Ohio you will find many owner built houses. With that in mind I have tried to visit anybody I can find who knows the in's / out's / tricks to doing it for this area. Some of it is a chuckle. A lot was to also gather as much info on what they paid. Many of these folks actually own the house out right after construction. The methods vary all over the lot as to exactly how they got it built. In general the regulations are very tame, in some counties almost zero. That portion of the costs is nominal. You may not even need a full set of drawings.
One lady I know built a house on family land. All the basic foundation / shell structure delivered complete for $26K. She is finishing up the inside a bit at a time. Very nice, pretty big house.
Another guy bought a small cottage and added on to it for a pretty big house, rebuilt a big barn all using local sawn timber, some of it apparently off his own land. Total cost they guess maybe $15K.
There are some examples of owner built using prefab's. One guy I know again got the land from the family, sub'd out the basement, got a prefab delivered, final cost ~$36K. Some of these good olde boys know how to work a deal.
You can still find some mom / pop builder type operations. They build under 10 houses a year, many might only do 3 or 4. Quality type houses, usually in or close to smaller towns, small town type lots. Costs vary with the year maybe something like $80 - 150K. Usually very nice houses.
If you look at all those categories, compare your area. Is land cheap, can you use local materials, is the regulation a zoo, what type of profit does a builder need to stay in business?
This last building boom it got wacko. Everybody could pass on the costs to the customer, they did not have to be efficient. I would be patient, learn as much as possible, see where you can cut costs, find the best contractors.
I figure if I can find the right land in exactly the right spot can easily build the dream house for something in the $30K area plus the cost of land. That will be with all the whistles and bells. Money no object. If you are crafty and can buy / prestock various materials a lot of it can be had at next to zero. The better builders will probably also try to score big on folks dumping materials at very low costs. The real way to save on costs is to be very involved. Determine how you can cut the costs in each category yourself. Every builder looks out for their own interest first.
The one that was the biggest chuckle is this guy and his wife have been building this very nice house way out in the woods. Been working on it in their spare time for about 3 years now. Basic shell all done, power and water in. So I get a visit, very, very nice. I ask all the questions. What type of permits? Duh, what permits, we never even told anybody we are building it yet.
There is still is an America.