Our cost of living is high, especially considering surrounding areas, but $12,000 would be a dream budget for projects I've done. While it's hard for "a charity to win that game", there are things a charity can do that a business cannot.

The example that comes to mind was a nightmare project I did two days on. The story was the foundation was bad, we had a terrible spring, the basement started torrent-leaking revealing mold and other dangerous things (it was finished, to boot). The water was up to your neck when I saw it the first time. It took four weekends (and a few Thursdays for some of the teams), I believe it was high 4-figures, most spent a month before on environmental-related -- high cost even when the services are being nearly donated.

Outside of that, We had a master electrician and plumber, a licensed architect who owned a local survey company, many former builders, and between them got the cement company donated labour on with nothing more than a phone call and an explanation. This was all done for no real benefit to those providing the services -- this was a small church program that if you called their direct line would likely take several tries to find someone who even knew we were affiliated with them. Almost all of our weekend labour were folks who had jobs/owned other companies and attended my church on Sunday[0]. It was the most difficult job that I can ever remember working on. My favorite part is that all of the work "us inexperienced jackasses" (those of us, like me, who hobby in this stuff but haven't done it for a living) had everything we did pass inspection on the first go. Generally, everything did, but the project was delayed for a few weeks because the mold removal was incomplete and (I think) the sump Radon system needed a near re-do, and I believe the latter one was something we had to pay someone to handle, originally[1]

[0] That's not always the case -- our church doesn't do the whole "we only talk with Jesus People" thing. I remember because this specific case, the owner of the cement company (initially, uncomfortably, probably out of fear we'd be interested in Bible-Thumping him) let us know he is Jewish. He stayed 6 hours after his truck left, hanging off the side of the house nailing in boards for the roof repairs (he looked about 80, I'd guess he was 70+cigarettes). Incidentally, he saved us thousands of dollars because the roofing company just ... didn't show up, phone disconnected ... vanished into thin-air ... and he ended up getting the entirety of a two-day estimated job done with another man and his 20-year old son.

[1] ...and I remember this specifically because we were really frustrated. Ended up that one of our "former construction" guys took copious notes, showed up the next day/ripped it out and re-did it rather than bringing back the bozos who cost a fortune and did it wrong. Certain that wasn't legal, but it passed inspection and it works. But the piles of stupid was that there was one guy who inspected each of the various things and for whatever reason, they refused to send him here one time to do each of the 5-minute inspections all at once, like makes sense for everyone involved. It wasn't even his fault -- the lone inspector had no control over his own schedule!