. - Looked at the property tax.

If they own it and are going to put it in that bank then offer to borrow the money from them and pay on a monthly basis to they get more money than they would in the bank and then avoid taxes too

If so, then a spreadsheet could probably do.Also do you do your own taxes or have a CPA?

BUT you have less red tape, no tax returns, DTI, or employment checks are required.

I am researching a property that is scheduled for tax foreclosure sale in Wilmington, North Carolina, New Hanover county.The law firm that handles the foreclosure for the county says that the property will come with a “non-warranty commissioners deed” but the paralegal could not really explain what that meant.The law firm also says that they WILL sell me title insurance at the time of purchase.

My understanding on this is that if you build it unpermitted, the benefit at that time is that your property value likely won't increase because the square footage is not assessed to increase the value of your home and therefore the property taxes.

If you have the other expenses, such as the property taxes, water and sewer bills, heating bills if the landlord is responsible for those, electric bills if there is a landlord account, and any other bills you as the landlord would be responsible for monthly you can total them up and see if they will be more or less than the $900/month rent your apartment will generate once you eventually move out of it.

Calling a broker to get a ballpark like @Chris Seveney said  or getting an online quote will always be the most accurate but if you want quick numbers - Nerdwallet has a "by zipcode" feature: https://www.nerdwallet.com/article/insurance/estimate-home-i...If you are working with a loan officer their different systems often auto estimate taxes and insurance as well - so you could ask them. 

Looking for accountant referrals in the Cleveland/Akron/NE Ohio area with strong familiarity in investment property related tax matters.I'm planning to purchase my first investment property shortly, but I need an accountant to do tax preparation for my current retail business this year (Form 1065) and personal returns.

It doesn't make sense be in a -$800 a month (at best) while paying a huge monthly payment with high property taxes.