Why does this happen to my basement bathroom sink?

What about it?

I have to clean this (what looks like remnants from dirty water) from my basement sink every few weeks. It and the rest of the bathroom rarely get used if that adds any context. I haven’t done any work to this bathroom since we moved in 18months ago.

I need to replace the face plate that goes here, but I’m not too sure which one I need to get. Any suggestions?

Is this normal for a shower drain install?

What about it?

See the attached picture, it’s a flat drain in the shower of a new home

Purpose of deck plate

What about it?

When you only have a single hole (no need to cover 3 holes) does the optional deck plate serve any purpose? What are the pros and cons to using it? Or is it just aesthetics/users choice? Thanks.

Vanity drain

What about it?

Home owner not a plumber so take it easy! PEX hookups were already there, also no room to get the AAV higher. Have a good weekend everyone!

Pressure regulator went bad - How do I remove the "top" of the old one in order to replace?

Snapped the plug, any tips?

What about it?

I was going to try to find a chisel a bit wider than a flat head to wedge in there. Any better ideas?

Is this the indoor unit filter that needs yo be changed? Only this one? Not the smaller vents right?

Whyyy

What about it?

Is this normal or like why did they set it up like this🫠

Not every builder is doing it.

Bathtub cartridge removal

What about it?

Hi, I’ve watched a couple videos on how to remove a cartridge in bathtub and picked up a cartridge removal tool. My cartridge doesn’t have a clip (this was referenced in a few videos). When I use the tool, making sure it is tight with a screw driver, it doesn’t connect with the cartridge. I’m not sure what I’m doing wrong? Thanks for help with this.