If you are listing yourself, find comps that your subject property beats out the water and list around that benchmark. 

I am willing to test the waters for awhile. 

You've definitely done your homework, as you know 20 degree delta T is the typical industry standard. 46 degrees is (substantially) unreasonable.To note; delta t and the equipment operation is highly relevant to the envelope that's being conditioned.

Is this standard?

The owner pays for all the bills currently 575 per unit, which include water, electricity, internet, and cable.

We put a lot of efford and attention into keeping basements dry, but we still have an occasional pipe burst or sump pump fail and see issues and when you get water in a basement; carpet can be dried and cleaned, it's the open cell pad that is holding on to gallons of water like a kitchen sponge.

Navigating the zoning requirements, dealing with Maryland Historical Trust limitations on what can and can’t be done to the property, and the financial burden of renovating the property to meet these standards have left us trying to figure out the best strategy so the property doesn’t just sit unused.If we decide to sell, we anticipate pricing it at around $70-$80 per square foot, which is an incredible deal for a property of this nature.We’re reaching out to see if anyone here might know of potential buyers interested in this unique opportunity.

If I am buying directly from a property owner, I sometimes not only pay all closing cost but also back taxes, water bills etc.

Interest rates are just one component of the economy and you have many different macro-economic conditions that impact housing such as job market, inflation, debt loads, lending standards etc. 

There are 2 options for this: standard, and rain refresh.