About this site

Andrew Flores is responsible for this site's research, calculations, source checks, and corrections. He is not a plumber, a gas fitter or a mechanical engineer, and nothing here is a substitute for someone who is. What he does is read primary sources carefully, put the arithmetic where you can check it, and refuse to print a number he cannot attribute.

That is a narrower claim than most cost sites make, and it is deliberate. A plumber can tell you what your job costs because they have stood in a hundred basements like yours. A researcher can tell you what the published evidence says, where it disagrees with itself, and which parts of an estimate are actually load-bearing. Those are different services and it seems worth being clear which one you are getting.

How the numbers got here

Every figure was pulled from a named page, quoted verbatim, and stored as a snapshot with the date it was checked. There are 106 of them, verified on 2026-08-06 and 2026-08-24 — more than one date because two sources were added after the first pass, and printing a single date for all of them would be tidier and untrue. The quotes were matched against the captured bytes by machine rather than by eye, because reading a page carefully and then transcribing a digit wrong is a very ordinary way to be wrong.

Where a figure is our own arithmetic, it says derived and shows the working. Where nobody publishes it and we picked a number, it says assumed and appears as an editable input, so our judgement is something you can overwrite rather than something you have to accept. The complete list of assumptions is on the methodology page and it is short on purpose.

What this site will not do

It will not invent a regional multiplier so the estimate feels personalised. It will not floor a negative saving so a payback calculation returns a tidy number. It will not fill a gap in a published series with a neighbouring state and hope nobody checks. Each of those makes a calculator feel more useful and makes it less true, and the second thing outlasts the first.

If you find a figure that is wrong, out of date, or attributed to a page that no longer says it, the contact page has the address. Corrections are made with a note of what changed and when.