Based on the roles you mentioned above, it sounds like you may already have your hands full.

The extra year can be used to dispose house if they don't exercise option.

Once the option is exercised, the current home owner is no longer the home owner, and the lease is gone. 

While the above comments are intended to offer advice for the landlord to recoup their lost rent, or successfully collect rent, there are some significant misconceptions about the role the military can play in this case. 

Is local market research just an exercise in futility?

You need to exercise good judgement and not be afraid in making your choices. 

I was recently hired by a full service brokerage (leasing, property management, investor relations, acquistions, etc.) and they use the time during the 3 week accelerated prelicensed broker class to determine what role you fit best within the company.

I have a tenant that seems to always exercise this option. 

Realtors still play an important role, of course, and I'm sure most can point to statistics that show higher average sale prices and fewer days on the market with a realtor versus without.

I may be misreading this, but from my experience of human nature and working with teenagers, if you see this young man as a "punk" or "jerk" and treat him like one, he'll fulfill that role.