@N M Clarke, i would suggest speaking to someone in the assessors office to better understand why such a large change was made.

I've been looking into self-storage companies to buy and I've gone through articles and videos on how do do it.

Buy and Hold ?

For the money you will pay to invest on the 1600 block of N 27th street, you are better off buying in Germantown/East Mount Airy where the fundamentals are better or spending more to be in a better neighborhood.

There is a sizable number of well-to-do folks coming over from Mexico and buying second homes or investment properties in the area. 

Building Equity: Part of your rent can contribute to the eventual purchase, helping you accumulate equity.Cons: Risk of Losing Money: If you decide not to buy at the end of the lease, you might lose the option fee and any rent premiums.

I would think that a lot of folks who were in it 2-3 years ago were in it for the non-performers, and we know how that market is currently.I'm not currently buying because my capital is currently deployed. 

I would call the city or go to their office and ask them.

And you cannot use it to purchase a primary residence.You can however use it to buy an investment property and later convert that into your primary residence to get a prorated amount of the gain tax free.You can also use it purchase and improve an investment property as long as the improvements are complete prior to you taking title to it. 

Never buy a property with the intent of changing a neighborhood or a city unless you have capital to waste.