Cash On Cash Return Question

[Bill Sobol]

My first property I am looking into after reading the Rental Property Investing Book. I don't have a huge budget. I am looking at a house in Pennsylvania. The price I would be getting it for is $115k. I am putting 20% down and would get a mortgage rate under 3.5%. After taking into account mortgage, closing costs, minor repairs, taxes, hoa fees, cap expenses, vacancy rate, misc fees my cash on cash is almost 20%. That seems very high and almost to good to be true but I think I covered all the basis. Any advice? Is it not as good as I'm thinking?