There are a great many factors to be considered when buying a lot and then building on it, as opposed to purchasing an existing home, whether it be a new home or a resale home.
Location is a very important factor and will likely be influenced by both affordability and your desired area.
Most city lots involve purchasing an existing home and then tearing it down, thus adding to the cost. You are more likely to find already vacant lots outside the city limits.
In either case be prepared to spend a minimum of anywhere between $100,000 to $300,000, depending on the location.
There are many costs involved in the building of a new home:
building plans
permits
escavation and
contracting costs
In addition, there will be what is commonly referred to as soft costs.
These include such things:
landscaping
paving of driveways
fences and other similar exterior items
The cost of construction of a custom built home can range anywhere between $100 - $180 dollars per square foot, making the cost of building a 2,000 square foot home somewhere in the $200,000 - $360,000 dollar range.
Most experts agree that an additional 10-20% should be factored in for unanticipated items, including upgrades.
Add appliances, decorating, lighting fixtures, window and floor coverings to this as well.
If all this does not discourage you from going ahead with the idea AND you have considerable financial resources at your disposal, THEN it can be a very exciting adventure and you will have the unique opportunity of building your very own Dream Home customized to your personal specifications and taste.
