This does create a bit of a conundrum if 1031 is a possibility for exit strategy. 

How would creating LLCs impact the houses’ mortgage, insurance, title, and tenant lease?

I suppose they are "retail prices" creating a 7-8% CAP rate overall.

Purchasing my first duplex in South Jersey and am looking for Real Estate Attorney recommendations in this area to help with creating and reviewing rental / tenant contracts.Thank you!

What I did for my case was to create a spreadsheet showing both scenarios.

Those inaccuracies create opportunities! 

You should be able to just create two separate urls, one for each of the options.

Go about to creating a lease?

I could only imagine the regulations you would have to jump through with creating a new airport. 

@Shane Jeanfreau if you will be seating on built up equity that you created by repositioning the asset you MAY be able to refinance the property after 6 or 12 months to 70%-75% (or more depending on your lender and the property) of Appraised value.so if you added sufficient value you may be in a position to have no money in the deal.