All else aside, given the amount of rent you could be charging it may be an idea to sit down and develop a long-term (2-4 year) budgetary plan for the unit/complex so that you can 1)gradually increase rents to a more uniform standard--as one member stated, "if they are all comparable units, there shouldn't be a drastic difference in the rent amounts" 2)eventually get all the units with equivalent or comparable upgrades (to keep things even with the neighborhood comps based on ammenities), and 3)ease your mind about the financial plan and trajectory of your complex (so you can just follow a predetermined plan and adjust when needed as time progresses).

I've seen a coffee cart (250  sqft) with a $2K/month least being pushed at $2M. 

Find a good agent, I'd get coffee with a few, and then get the mortgage process rolling. 

I'd come up with a good list of questions you have and just ask, because this isn't likely to be an ongoing business relationship unless you bird dog, the flipper may just talk with you no strings attached.

Good luck and hit me up if you want to meet for coffee.

I rented it out several years ago - I can keep it rented, although quality can be an issue at the beach.#3) Land in same place as #2. 

I already have 2 roommates lined up that would rent rooms and finding more if space permits would not be an issue.

An S-corp would be an election of how this LLC is taxed, and you should not make such election when you start.

However, it is impossible to be an expert in every area.

If you think that by handing someone money and having a piece of paper that you have since lost, that you have legal right to the property, well, this will be an uphill battle.