On my original patina 1970s bikes, I've been struggling with carrying water and the tool bag. (I take a tube, the basic and typical tire and Allen tools, a CO2 set-up for inflation, and run a LED tail-lamp hanging off the bag for safety.) ~ All fairly typical I think.

And two water bottles for my long rides.

Knowing that vintage clamp-on bottle cages will really damage my paint, that is not an option. And no way would I drill the frame and put those expanding nut-zerts in there.

What I did on three of my bikes, I've got the Profile design seat post mount double bottle cage set-up, and stuffed the tool bag between, but that is really a tight fit for the bag. (My 1972 MERCIAN VINCITORE in this image)

Please show us your set-ups for solving this on bikes with no bottle mounts on the frame.