OK, not seeing this as the end of the world, but there are some troubling things (based on what I see in Portland and watching news):1) No inventory means in PDX people are reaching beyond FMV on housing and abetted by cheap loans2) Debt service issues - I'll take the extreme, look at retail in NYC, there's lots of space empty at $80/SqFt.  

I have the top 3 units already rented out as residential space.

I investigated enough to learn the parking rules and was pleased to see your project has exactly (and no more) the amount of required parking spaces for the unit mix you've proposed.

Maybe they are hanging on to the space for the sake of putting up their Millennial children, who are, of course, more living with their parents later and later into their twenties. 

There are also major plans to build restaurants/bars/shops under condos and various parks/outdoor spaces in the Potomac Yard area. 

If the 12' section is in a crawl space or basement and is easily accessible and isn't leaking, don't disturb it.

@Theresa HarrisLocksmith is the best route but not free.Check all of the windows, I have had to crawl through one or two before.For the cost of a stamp and a $1.69 key at Lowe’s the owner could mail you a key.Then you can get into jimmying, drilling locks, kicking doors in, etc. - but all of those are more likely to get the cops to show up

Seasoned park investors are more likely to buy larger parks, so that is not a fair question since there are only 10 spaces there.

The property out in Mass is a small store with a garage,a small space that a church rents, and two units above.

Sometimes it’s better to go slow and make sure you have the “mental space and capacity” to take on the next phase.