Biased opinion as my experience has all been in the Land of 10,000 Laws, but depending on where you are does 100+ year old electrical methods still qualify for typical lending and a rental certificate? 

Please speak with your attorney and have them review the leases for each tenant then forward to each tenant an estoppel certificate verifying that the language in the lease is correct, there are no defaults, etc...

Once it's about 2 years or a couple tax certifications, now I'd consider mailing the lead.Next, I think a big thing if you're working on a budget is less about your list and more about tightening your list.

Residential properties, inventory, securities, trust certificates, corporate stock, or partnership interests cannot be exchanged under Section 1031 Internal Revenue Code, 26 U.S.C. § 1031.

@Samuel S. try and send the bank a Certificate of Insurance listing just your personal name. 

Does it make it enforceable: NO.Unless you use some authentication in the chain of signature where it can be traced to a certificate that has been verified as owned by the person in question, these websites are useless. 

Is getting the certifications worth it?

Saving money to invest in yourself such as for community college or a certificate program could also be a good use of your savings.

When he was asking the inspector about the stairs today, the inspector began yelling at him, saying he didn't care about what we did and that he would withhold the certificate of occupancy.

You can have your attorney get a zoning certificate from the city to see if it comes back as a legal two flat or not.