I might be in a similar boat to you.
I hate the idea of paying a subscription for software I can build myself.
Currently, I have an excel spreadsheet and it’s in OneDrive, so I can access it from my phone or ipad when I’m bidding a job.
I just enter my count into a preformatted count sheet, it does the math on another sheet I’ve set up as a calculator and automatically populates totals into another pre-formatted sheet.
This is something that’s taken me months to develop because I’m no genius.
It’s excellent because as soon as I’m done the quote, I can email it to the client.
It falls on it’s face automation wise when it comes to actually emailing the quote and storing the quote.
Currently I have an estimated jobs folder in OneDrive and I create a new folder for each client. Then I save the copy of the spreadsheet I was using to price their job in that folder, as well as the PDFs of the quote.
I’m not super busy, so it’s not a big deal currently (actually I love that I never have to think when I’m pricing). Once I grow more, it’s probably going to be a pain, and I’ll either hire someone to make it into a web app, or subscribe to something.