From what you say is that they are not legal to be there based on today's zoning (non-conforming), but they are legal based on when they were installed (legal).

I have installed a mailbox and address numbers.

In my case, as a DIY landlord, I'm in this for Cashflow Forever and Real Freedom.

That's not a 'bad' rate to borrower very accessible capital that has to be repaid over a generous 360 installments. - Most DSCR loans come with standard 3-5 year early payoff penalties.

If you have other properties in that same county, you could probably just change the property descriptions as a DIY Quit Claim.  

I'm looking to install a new furnace in my duplex in Cincinnati OH. 

Depending on the facts and circumstances of the agreement, it could either be treated either1) the sale occurs as of the original agreement date, and then your taxable gain is generally spread out over the life of the principal payments as an installment sale (although I should mention any depreciation you've taken on your property could affect this), or2) the sale does not occur until the lease option is exercised, and gain reported at that time.

In this case, the material cost AND install costs will vary, so having an idea before you even meet the contractor is important.  

I can tell you that their involvement is on the financing side only, as they work with local installer partners on the back end with the installer managing the customer relationship so Mosaic wouldn’t typically interact with the customer directly which might explain the gap in the line of communication.

It would involve installing new dedicated water pipes per unit, three combi water heaters (to replace the two conventional water heaters and the central boiler), and three gas and water meters.