I know they have both received their respective letters because the upper tenant responded promptly with the contact info I requested.Upper unit tenant has been awesome and super easy to communicate with.

Leave a gap at the bottom, a little less than you base board (typically 3.25”), then just partly fill every 12 to 16” with your drop /scraps.

Using one off mountain will not get your offer as well received because off mountain agents do not like to come up for inspections, etc. and dump that work on the local agents who resent doing it and not getting the commission for that part of the deal.Look at the zoning. 

The size of the house is pretty typical of a lot of county guidelines. 200 extra SQFT is not that big a deal IMHO.The property is a zoned SFR1 or whatever the New York state zoning codes are.

My goal is to come up with a way to avoid interest payments as a buyer and/or a seller while still providing or receiving financing.

Here's how it typically works:Purchase a Property: First, you'll need to buy a property with a basement that can be converted into a livable space.

Loan costs would be higher than your typical loan but if done correctly those dollars would yield a much higher return than the cost of the loan. 

My worry with leaving the local agency is the personal attention that guests receive when they call.

Yes, it is typically normal unless there is an agreement with the accountant where you will pay him to go through all your receipts, sum up the amounts and categorize them.It is confusing from your post because it seems like originally you mentioned not having your income and expenses properly categorized but in the end you mentioned providing it to him.

Being a wholeslaer is having a business.You are in the business of finding and buying land/contracts for a short duration and then immediately selling them.One typical expense for a wholesaler is all the advertising costs to find motivated sellers.