At the moment I am saving up for a down payment but still undecided on whether to target single families homes or multi-family using a FHA loan.

Currently, I am undecided on my career path.

or a couple of profitable Airbnb units (location undecided).Questions:Is it advisable to wait a few more years before selling the NC house?

I am currently undecided on which property type i prefer for my first deal.

If you're undecided about where to invest, I would definitely suggest Columbus. 

I have a fix-and-flip deal lined up (or possibly fix-and-hold.... undecided).

In early 2011 I had been listening to several podcasts on investing and real estate in and had been saving up funds for making my next RE purchase but I was undecided as to whether or not I wanted to buy another fixer upper in my town or pursue another RE strategy.

I know that it is gone, but in my mind that creates instant value/equity/price/something that's worth analyzing.We are undecided about staying here or leaving within a year, so we are looking at both options of buy-then-sell-soon (basically a flip, I guess?)

A bit undecided on whether to take the proceeds of the sale, pay capital gains taxes on it and invest the balance or do a 1031 exchange and replace the property with another. 

I'm undecided on how I feel about the whole refinancing and leveraging tactic, but it is starting to make more sense to me.