I am assuming that since you just looked at it, this is an old survey done for someone else.
So Boracay’s advice on finding a good steel surveyor
is exactly right!
Keep in mind that steel boats rust from the inside->out, so get the proper equipment
to inspect every inch of the inside structure frame spaces (especially the inaccessible areas fore and aft, where water can lie) and focus on the quality of inside coatings as a key indicator.
As well as construction, Type of steel also makes a difference in required scantlings (thickness)
My own SG is made of the higher strength, self-sealing Corten Steel, which allows for thinner plate but the Dutch builder
overbuilt (as they usually do)
After 29 years the bilges are like new but I was worried about electrolysis
so last year I had the hull sandblasted to white steel for detailed exterior inspection
I first scraped off the years of antifouling to identify any areas of poor adhesion before blasting a side each night
Perfect, except for this small dime sized spot near the stern quarter. It was mostly cosmetic but I burned rod anyway.
Found out that under the lazarette were about 8 large zinc anodes that had been used for ballast.
One anode had shifted and its corner was touching the exact spot where I found the blemish. (after 28 years)
Point I am making is that you should research
what you have and know that steel is quite easy to live with if it was constructed well and you follow basic maintenance.
Good luck with your search!