Inflation and restoration costs

The discussion concerning the 191 and the information regarding the prices involved in a quality cosmetic restoration provided have made me wonder what costs were when the assorted equipment at museums such as the Colorado Railroad Museum were originally constructed.

$13k for some tongue and grove wood to be sourced. What was the price of the same material when the reefer was built new? Can these prices even be obtained?

How much of the current prices are due to loss of skills and scarcity of material?

How much of the rise in prices is due to inflation caused by - insert reason here - that may not be what I've heard economists call natural inflation?

We've all heard the joke how do you restore a steam locomotive? Easy. All it takes is cubic yards of money.

One of the reasons diesels replaced steam is the cost of maintenance. Steel rolling stock replaced wood for a lot of reasons. Could one have been cost of maintenance?

Building railroads costs cubic yards of money.

How much would it cost to build and equip the Silverton Branch today and when adjusting for inflation, how would the cost today compare to the cost of when the branch was built in 1880 and the exorbitant price of $100,000 a mile for some stretches.