It would be nice if you had a contact who was an actual mason not a marketer.  1930's construction is rare so maybe they cut some corners it was a global depression.  

Contact the utility provider and get a historical average based on the last year of use.

Through your local bank that you are using, are you reapplying for each new home for a seperate construction loan or are you setup as a credit line with them and just submit a new budget for each new home 7 mil credit line  ... new budget for each plan that has been pre appraised in the MAI at the beginning of the project.. they did have to update the Mai last summer but again did it at their cost not mine.. banks have to paper their files.. even though we are selling the same floor plans for 100k more per plan than the original numbers came it at and bank has been paid and has all the closing statements showing this data..

Happy to share some contacts with you if this is something that interests you. 

Hey Dominic, I have some good contacts to help you out.

And if you have been keeping people's contact info, you could pass that on to him as well so he can send out a change of ownership letter.it's just going to depend on the specific property and the specific buyer that wanders along.

Ourcurrent approach involves identifying possible contact information for thelisted owners and calling multiple numbers, but this process is time-consumingand yields limited results.

A contact of mine has been thriving with STR investments in suburban Chicago, targeting guests visiting for conferences.

Have her call a few churches or similar organizations to get contact info for who to talk to.

Then I started to contact brokers that bought and sold Apartments complexes and proceeded to 1031 exchange all my Condos for Apartment complexes and told my story on BP Podcast 238 in 2017.