Not an exhaustive list, and not every item matters on every site. But this is where the cost differences between two lots almost always come from.
Access and staging
Whether trucks, concrete and equipment can physically get to the build area, and where materials can be staged.
Slope and site work
How much cut and fill the site needs, and what that does to the foundation, drainage and retaining.
Soil and foundation
What the ground will support, and what kind of foundation that implies. This is where a cheap lot often stops being cheap.
Utilities
How far water, sewer, electric and gas have to run, and who pays for the extension.
Sewer or septic
Outside city limits this is often septic, which needs its own area, soil testing and permit.
Drainage and floodplain
Where water goes in a heavy rain, and whether any part of the lot is mapped as floodplain.
Trees and clearing
Which trees are protected, what can come out, and what preservation requires during construction.
Restrictions
Setbacks, deed restrictions, HOA architectural requirements, and historic design review where it applies.
Rules differ depending on whether the lot is inside San Antonio city limits, in unincorporated Bexar County, or in a Hill Country municipality with its own requirements. We confirm what applies to your specific property rather than assuming.