Help with understanding Cashflow analysis

[Armando Montrond]

Rookie question here, Ok I know cashflow is pretty tough to come buy now a days, but I have been putting some deals through the rental property analyzer (single families) Here is what I am putting in for parameters. These for the most part are not real numbers I am just trying to find what is the minimum i need to get cashflow positive 

6% rate with 20% down, 

8% vacancy,

5% capex 

5% maintenance. 

400 for Gas,electric,sewer,trash 

Im doing no fee for property management right now as I will be managing this myself. 

I am looking to do MTR and inflating the rent to 2400 a month

I am finding that in order for anything to cashflow positive with these numbers, I would need to find a property with a purchase price of around 150K or less. I know SF will not cash flow as much as MF, but it cant be that in order for anything to cashflow I need an extremely cheap property with an absurdly high rental rate. What am i doing wrong here or are the numbers just the numbers and if I want cash flow i need to find something cheaper than 150k or do a multi family?