I laughingly suggested we put a gutter in that corner, inside the walls, as water had been running inside the wall long enough to reduce the vertical post to dust.  

Way to hard to clean food and dust off of. example:https://www.homedepot.com/p/MSI-Alaska-Gray-Splitface-12-in-x-12-in-x-10mm-Marble-Mesh-Mounted-Mosaic-Tile-ALGRY-SFIL10MM/206741880Too busyhttps://www.homedepot.com/p/MSI-Magica-12-in-x-12-in-x-6mm-Glass-and-Stone-Mesh-Mounted-Mosaic-Tile-SGLS-MAG6MM/206741857Very uniform and neutral, adds design fare.https://www.homedepot.com/p/MSI-Honeycomb-Hexagon-12-in-x-12-in-x-10mm-Natural-Marble-Mesh-Mounted-Mosaic-Floor-and-Wall-Tile-HONCOM-2HEX/205307895

Try brown bagging.

@Nurzhan Abenov congrats on getting the first one in the bag!

Pre-finished hardwood a bigger item but the bag for the buck can be huge.

Simple renovations many times for dust and fluffs will not require inspections but a permit is required at a minor fee. 

I know two brothers in my area, who started investing the same time we did, bought 2 triplexes like us, and then sold it about 8 years later, and bagged over $100K appreciation for each, totaling $200K.

The younger EMT told me it was the first time he'd ever come in on a call to find help on the scene already in blue gloves.The older EMT actually stole my roll of paper towels out of my bag to clean up blood with.

One year we discovered that mice were in our "private" closet, eating boxed and bagged food, while nesting in some towels. 

The property should be made back to what it was when you agreed to rent it.Also, as safety issue, it could be a lead, asbestos or even a mold/dust issue.