Evaluation starts with three non-negotiables: a zero-step entry, 36-inch wide doorways, and a full bathroom and bedroom on the main floor. If the home lacks these, you must budget $30,000 to $100,000 for structural changes, depending on whether walls are load-bearing. If the topography of the lot makes a ramp impossible or the foundation prevents a curb-less shower, the house has zero aging-in-place potential.

Standard interior doors in older homes are often 28 or 30 inches wide. A standard wheelchair requires a 32-inch clear opening, which usually means a 34-inch or 36-inch door frame. Widening a single door sounds simple until you realize the light switch, the electrical outlet, and the HVAC return are all in the way. Expect to pay between $800 and $2,500 per door to fix this, and that's assuming the wall isn't holding up your roof.

Hallways are the next hurdle. You need 42 to 48 inches of width for a comfortable 'forever' home. If the hallway is narrow and ends in a sharp turn into a bedroom, you’ve created a geometric dead end for anyone using a mobility aid. When touring a potential home, bring a tape measure, not a paint swatch. If the hallway feels tight now, it will feel like a literal trap later.

Then there is the 60-inch circle. This is the amount of clear floor space needed to turn a wheelchair around. Check the bathrooms and the kitchen specifically. If you can't draw a five-foot circle on the floor without hitting a vanity, a toilet, or an island, the room will eventually require a total gut renovation. These aren't just 'preferences'; they are the difference between living in your home and being forced into a care facility because your house became an obstacle course.

Most people think 'accessible bathroom' means a few grab bars. It doesn't. A true aging-in-place bathroom requires a curb-less shower where the floor of the bathroom is the floor of the shower. To do this correctly in an existing home, you often have to 'drop the subfloor'—literally cutting into the floor joists to create a slope for drainage. This is a $15,000 to $25,000 project that requires a master plumber and a very skilled contractor.

Look at the toilet. Is there enough room on at least one side for someone to stand and help you, or for a 'lateral transfer' from a chair? If the toilet is wedged into a tiny 30-inch alcove, it's a failure. You need at least 18 inches from the center of the toilet to the nearest wall, but 36 inches of clear space on one side is the gold standard for long-term safety.

Don't forget the 'blocking.' In a new build or a major renovation, you should have 2x6 wood blocking installed behind the drywall in the shower and next to the toilet. This allows you to screw a grab bar into solid wood later on. If you're buying an existing home, ask if the walls are plaster or drywall. Screwing a grab bar into old plaster without blocking is a recipe for a catastrophic fall when the bar pulls out of the wall under your weight.

You can change a floor plan, but you can rarely change the earth. If a house sits five feet above the street level with a steep, winding concrete staircase, you are one ankle sprain away from being a prisoner in your own home. A 'zero-step entry' is the holy grail. This means at least one entrance—front, back, or through the garage—has no threshold higher than half an inch.

Check the grading of the lot. If the house is on a slab, you might be able to create a 'ramped' sidewalk with a gentle 1:12 slope (one inch of rise for every 12 inches of length). If the house has a high crawlspace or a basement, you might need 30 feet of ramp to get up to the front door. Most residential lots don't have the space for a 30-foot ramp without it looking like a zig-zagging fire escape.

Lighting is the final, often ignored, piece of the site evaluation. As we age, the pupils shrink and the lenses of our eyes yellow; a 60-year-old needs three times as much light as a 20-year-old to see the same thing. Look for a home with massive natural light and the capacity for high-output LED recessed lighting. If the house is dark and moody with small windows, your risk of a fall increases exponentially every year you live there.