I currently own a retail building I purchased years ago. 3 years left on the loan with a sub 4% interest rate.

Hard money loans typically come with higher interest rates (10-14%) and often have a balloon payment at the end of the term.

Way too much gambling/luck aspect to it and even when you win for the year the tax rate is awful compared to long term gains. 

I was able to increase my monthly income rate of $1800 to $2300.

higher rates, but sounds like it fits your situation.

I believe that double what the rent currently is a fair rate for the market. 

There's no reason to jack up tax rates just because a house is used as a rental rather than a primary - all it does is inflate the rent at the renter's expense. 

@Dominique Coffin,This is much more common in our current interest rate environment. 

As a notary or NSA, you CANNOT explain anything to them except a general description of a document or where to find things such as the rates, terms, etc because that would be considered illegally practicing law.

Hi Dany, Check the estimated rental rates on Zillow.