@Wiley Hood DIY cost segregation tools like KBKG can be cost-effective for simple properties, but they lack the precision and audit defense of professional studies.

They should be found early on by talking to other investors or your investor friendly Realtor.It is through effective property management that your money is made besides buying well initially.

Are there any cost-effective ways to handle this situation legally?

In Portland for example we are not allowed to increase rent more than once in 12 months, and it must be less than 10% increase in "effective rent".

Really about growing a strong portfolio of solid deals.Now that being said, if you are a high income earner, well qualified, and can't find reasonably good deals: (i) you can connect with a well connected real estate agent for off-market deals; (ii) you might do a very narrow cost-effective cold call or letter writing.

We might  be able to plot on google maps once we have some data.  

Quote from @Frank Barletta: It is more cost-effective and practical to install a large-size TV and get the Nintendo, Super Nintendo, and Sega Mini consoles.It comes with games preloaded, legal, and each to swap in case something breaks. 

And, capitalism works to lower housing prices when this process is allowed to go into effect. 

Although the percentage of the increase is large, the determinative factors are whether the resulting rent is so great as to shock the conscience of a reasonable person and was effected for the purpose of compelling the tenant to vacate."

The main issue is a consistent lack of effective management and oversight.