It really depends on what the putty fills. Covered up rust holes will reappear in no time flat. It would be unreasonable to expect a 55 car not to have some putty in it.
The car is worth what you want to pay, it all depends on your negotiating skills.
putty or bondo skim coated over properly weld patch panels (no pin holes)are no problem.i do bodywork my repairs on my 62 ford galaxie are 8 yrs old and dont show no bubbl es or rust.
I Have a 1955 Ford crown Victoria , Calif. car, no putty , straight and solid @13,ooo. located in So. Oregon. Be sure and ask your wife first.541-582-8966