They need to be drained cleaned and refilled after every guest but other than that they are generally low maintenance. 

The other one has none of that and is circling the drain even though he has all the money he could need.Agree with others here that you need to find what drives you.

Inspect plumbing and drains are working correctly.  

If it took external income from somewhere to fund critical expenses associated with a property and that income vanishes and isn't readily replaced, someone will have a strong motivation to sell when reserves get drained.

Unfortunately, there is an easement (storm drain runs under the other lot) and the area is a designated so that all properties must be close to the sidewalk which is where the drain runs under so cannot build a property behind even though there's plenty of land. 

Heres the reality the flood zone maps are old some over 40 years, development changes the way the water would normally drain especially with more concrete which doesn't absorb water.

The discharge hose often needs an eyelet hanger screwed in so the hose will not pop out of the drain and water goes everywhere.

Cheaper solution might be finding out where the water is coming from on the outside and then create a French Drain around the perimeter of the house.

If the took a bat to the place have you checked the plumbing to make sure they didn't do the ol cement in the drains trick?

There is also a french drain system that is completely clogged up that we will have to clean out.