If so, would it make sense to try and sublet it, continue renting along with my two roommates, or try to improve it and either give other tenants a lease option (lease option "sandwich" described in Brandon's book) or exercise the option and sell when the time comes.  

Along with his suggestions I would recommend doing a little research into basic SEO practices.

They may continue to call if you don't answer but will eventually tire of the exercise or will decide to leave a message.

Hi BP, Searching around but have not been able to find an answer to this question:For example I get property from seller with a L/O  and then sell the option to tenant/buyer for my fee then get out of the picture. Aft...

The due on sale clause can not be exercised by the lender as long as title is transferred to a land trust where the borrower remains a beneficiary. 

Until you have more tools, this should be a safe place to practice. 

I live about 10-15 minutes away from our properties, but running over there to wait around to meet a prospective tenant isn't always practical.  

This is a great exercise as it gets you thinking about all the types of expenses (ie. will there be a prop. manager, what will you allocate for repairs and maintenance, cap ex, utilities, etc. 

In the area I primarily practice in, short sales and foreclosures can take a long time to process so it might not be the agents fault at all.

This will be much more seamless and quicker than trying to find a non owner 4 unit 2nd which is practically non existent as far as I know.