My goal is to keep flipping houses and start a business while sitting on that property but I'm unclear how to go about it.

It's 1am and I'm sitting here obsessing over granite countertops ;) Thanks for letting me know about your rule of thumb!

Lots of times banks just let properties sit or even start foreclosure and never finish.

Are you sitting in a pile of money and able to close in 5-10 days? 

I would say it depends on just how "move-in ready" you are expecting.If someone is sitting on a property that is in relatively good repair overall, with the exception of some paint, flooring, and minor kitchen updates (countertop replacement/cabinet refinishing) for example, as a result of inheritance or a property that may be more of an afterthought for whatever reason, then perhaps through direct mail you may uncover a handful of decent leads/deals whose owners haven't necessarily yet put the wheels in motion to get rid of a property that they may consider selling once they are given a slight nudge.

Natalie, I highly recommend pursuing your real estate license, you won't be able to sit for the exam until you are 18, but you will be able to take the classes and study.

If you want it passive, start looking for a property manager as soon as you can and factor it in in your cashflow equation.If you want to handle the property management, I'd sit down with a RE attorney to educate you regarding landlord-tenant laws and help you put together your lease and screening clauses.

There are always deals, if it were me I would sit this one out.  

I don't know...1) the cost of developing the landThere is an old house that sits on one part of the land so I assume it has utilities/sewer lines2) the cost of the building - for high end townhomes, should I use $100/square feet or is that too low3) what will be a typical ROI that you will say "Yes, this project is worth it."

I just have no idea what it should look like or include and we are ready to sit down with a few family members to make the "big ask"!