If you're interested in installing heat pumps, there is a similar open data initiative started by some redditors to aggregate heat pump pricing quotes.
https://docs.google.com/spreadsheets/d/1hBebytdBOzLQ4eoAbdFQ...
https://docs.google.com/spreadsheets/d/1hBebytdBOzLQ4eoAbdFQ...
I recently paid 325 euros (about $350) for a unit and 200 euros (about $215) for installation. They are cheap Chinese units but the quality is good in terms of performance. This year they might be even cheaper.
Note that 25% of those prices are tax.
You can buy a single head mini split for under $800 and the tools to install cost under $200, which you can reuse.
If you pick a good location (room with an exterior wall), the install is trivial.