Can I build here?

The size of the lot is the least important number. What actually decides what you can build is the zoning classification, and the setback requirements that come with it — how far any structure has to sit from the front, side, and rear property lines. A five-acre lot zoned for half-acre minimums with generous setbacks can be more restrictive in practice than a much smaller lot with none.

Easements are the next thing that trips people up. A utility company, a neighboring property, or the county itself can hold the legal right to use part of your land — for a buried line, a shared driveway, a drainage path — even though you own it outright. That strip is usually off-limits for anything permanent, and it doesn't always show up on a casual walk of the property.

Then there's what's underneath and around it: floodplain designation, wetlands, steep-slope or soil restrictions, and whether public water, sewer, and power actually reach the site or would need to be run in at real cost. A lot can be zoned correctly and still be far more expensive to build on than it looks, once you account for what it takes to get utilities to it.

The honest answer is that “can I build here” is really five or six smaller questions, and the only way to answer all of them with confidence is to check the specific parcel — not the neighborhood, not the listing description, the actual lot.