Should I require both of them to pay application fee or only one fee?

Looking online and running numbers when you aren't looking at anything in real life will never give you the confidence to pull the trigger.

@Cynthia Fuentes reality check you may not want to hear:How will you succeed when you've been in the business for 11 years, but don't know the licensing requirements - or a better place to research than asking a bunch of strangers?

LLC is not required to start to invest.

Finally once you have made the macro considerations then you can use the spreadsheets to analyze deals and scenarios which there are multiple templates online, or find an agent that will do that for you.

Did you get an actual quote or you took the numbers from an online source?

I can also do a lot of the re-model work if required - ie, full demo, new tile floor install, custom tile shower, tile over tub, kitchen tile backsplash, etc.

But unfortunately you can only use the purchase price of the new property to determine if you have met your reinvestment requirements. 

I hire a company to do the advertising required.

Your offer to purchase should include a requirement that the Seller provide all documentation and agree to sign an estoppel certificate (also called an estoppel form or agreement).