Sounds about right. A PT wood frame is about the least expensive part of the whole project. Why anyone would want to throw thousands or tens of thousands of dollars at decking, rails and labor over an old frame is beyond me. It's like building a Ferrari around a Geo Metro.All this talk is just bunk. No matter you do to make the new wood the same height as the old wood the new wood will shrink, than all the efforts are thrown away.
Tear out the old and put in all new.
It took us 3 hrs to tear down 400 sq ft and set it by the road. Took an other 4 to reframe it. It will all move together.
I'm sure to the super pros around here we did something wrong by not taking at least a week.
You don't put new wine in an old flask and vice versa.