LLC's can last for multiple deals/flips/projects. 

With low owner occupier financing the cash on cash returns can almost be infinite, so you will also want to include gross rent multiple analysis as well--how many multiples of the purchase price are in-place or estimated annual gross rents?

Best advice would be to partner with a broker who works with multiple hard money lenders, understands their guidelines, and can help place you in the right program for your situation and needs.  

Like a poker player who folds most hands, it's not unusual for an investor to look at many hundreds of houses for every one he buys.

If the mortgage is secured by a second home or an investment property, the multiple financed properties policy applies.

What questions do I need to ask when analyzing the purchase of multiple single family properties?

Hiring a contractor for multiple jobs is fine, if they're good at what they do2.

Does anyone have any recommendations on an App (software) that can help track multiple project expenses? 

Are there multiple leaks?

@Steve Rozenberg multiple streams of income and the pursuit of financial freedom.