How to do CMAs for historic homes

[Tim Wilkinson]

Hello all,

I wonder if anyone has experience determining ARV on a home that is in the National Historic Register. The home I am looking at was a mid-19th century railroad depot for a town in MA.

Any rehab on exterior will be very costly, including windows. 

I want to be sure I can determine its value before giving an offer. 

It is in one of the most desirable towns in MA and is several hundred feet from any tracks, which are still in use.

Thanks!