Usually years of accumulated silt have filled the clay weeping tiles, the earth on the outside of the home is pressed tightly to the concrete foundation leaving water no where to go.

@Kyle Davis   depending on where it is.. familiarize your self with   " Yazoo Clay"

You print all that on a peace of paper or put it on tablet and ask them what they think would be fair considering what the market is and that way you are going to make them raise the rents on themselves without them being frustrated and you putting it on your shoulders.Good luck.

It was a waste of $10K, because the sinking was probably just caused by the clay soil being dry those years.

Can you sit up in bed at night with your tablet or laptop?

Which per my comments above includes $$ flight time, where flight time being like a clay pigeon in a shooting range. 

Once I discovered from a friendly corner conversation that the neighborhood was built during the post-WWII metal shortage and all the sewer pipes were made from clay.

The necessary equipment should cost around $2,000 to $2,500 (including a fast tablet: iPad Air 2) at a minimum.

The tiles I buy is the porcelain type, stay away from the red clay backing tiles from the box stores.

Sorry, that was for @Clay Manship .