I've restored a couple, (750/550) and kept up with expenses in a spreadsheet.
These look pretty good, but still not perfect, not Concours level.
I have way more in these bikes than I could recover. I kept up with everything that I needed to get the jobs complete (tools, cleaning supplies, paint, things like evaporust, simple green, etc.)
But, as someone who recently retired, I was looking for a keep me busy hobby, and I found something I love to do. I use to ride bikes/race bikes about 40 years ago so I decided to get back on one.
Am I looking for a 3rd bike? I will buy one if the right project comes along, but am being more discerning this time around.