You can certainly build a new home instead of buying an existing home. This video points out that there is normally not a scenario where a new home is lower cost then buying an existing home. The upside of a new home is that it is NEW and then you wont have maintenance due right away and some existing homes may have work to do on them soon after buying. There are many reasons to buy a new home but it is not likely that the purchase price will be a lower cost.