Some other factors to consider - How long are you planning to hold this property?

What kind of property are you considering, SF, 2-4 MF, or 5+ MF?

A 30% above the cost of non-renewable energy was, at that time, considered marketable, more than that and they did not generally build after permitting.BTW, on government land leases there are requirements to mitigate impacts, so replacement land is required if the land used is habitat for certain species. 

What would you consider a good minimum profit margin?

I'm starting to realize that investing is something I want to consider learning for long term as I spend more time in this industry.

They love the nostalgia of it and wouldn't consider replacing such an important and historical thing.There is no script that will lead you to success in this, but friendly and collaborative will help.

I was originally drawn to it because I wanted to have one place where all my tenants paid rent and where they had the option to set up auto payments. 

If you’re set on a duplex with minimal rehab, an investor focused agent should have a strong network of contractors who can give you quick quotes, so you don’t wind up with any pricey surprises.

Most advisors consider the two (2) year holding period mentioned above to be very safe, but remember it is your intent that matters. 

Technically it would be best to get a C Corporate or S Corp. to flip properties and since you are considered a dealer if you do several properties a year and this could have negative tax consequences in an LLC.