I know this topic doesn't belong in Airframe. But, going through AOPA as I have for several years, this year the results are far different. In the past to insure my 1947 108-1 assigning a value of $25k, my insurance went up by almost $300. Also one company said I needed a medical EVERY year for a class III, and I needed a Flight Review EVERY year. I turned 75 and this is the problem. I shouldn't complain too loud as I can still get insurance for about $1,200/year but it was still a jolt. thought I'd pas it on.
A class 3 is valid for 24 months per the FAA. In case it helps, I use Falcon Insurance through the EAA.