Without any cash it is unlikely unless you can find a 100% seller financed deal (they do exist, I just did one a few months ago).

Second, there is sewer line insurance that the buyer can purchase (literally only a few dollars per month) which they can sign up for if/when the line fails, and if/when it needs replaced.  

How high can housing prices in the City of Detroit go?

Can you count purchases made by friends/family as expenses?

That allows the timing of the renting much easier as you can move into the new house, then rent the other, then refi the bridge loan into a perm loan. 

Quote from @Max Yuan: I think we can agree finding good quality off-market leads is not easy.

These will give you the out numbers, and then you can work backwards once you know the repair costs.

I have found that the profit margins are very low in this model if the house is in a C/D neighborhood because you are limited to the amount of rent you can charge for each room.

There have been some very good spreadsheets posted on here in the past that you can search for and find.A spreadsheet is going to be much easier to use and play with different numbers than an app.

These can help you build capital while gaining valuable experience.