What problem are you solving? More bedrooms, a bigger kitchen, a home office, or space for a parent moving in all lead to different sizes, layouts, and budgets. Start with the need, not the square footage.
Where will it go? Building out, up, or converting existing space like a garage or porch each has different costs. Setbacks, septic fields, slopes, and trees on your lot all affect what's practical.
How will it tie into the house? Rooflines, floor heights, and exterior materials need to match so the addition looks like it was always there. That usually means careful framing and roofing work where old meets new.
What's your budget, including a cushion? Plan for a contingency, especially with older homes, where opening a wall can reveal repairs. A written, itemized estimate shows exactly where the money goes.
Who's building it? Additions involve site work, foundation, framing, roofing, drywall, and paint. A crew that handles all of those keeps the schedule tight and the responsibility clear.