I stumbled upon this post searching for some data and I can't resist commenting.

I know you have heard a thousand times but couldn't resist! 

If the carpet needs to be replaced in the living room or other common areas, I'd recommend a very durable, moisture resistant flooring. 

It is resistant to steam and moisture If you Google "leaded glass windows" you will find all the information you will need.

For one offs, I have been lucky to find them on Amazon Marketplace.I do not do flips, but if we need a clean out, a local guy with a truck.Can't resist.....silly joke, but...

Unless I miss my guess, your electrician is going to tell you to put in a second switch inside the house and run it to a GFCI outlet (also in a weather-resistant box) outside.

Your slab is subject to bending stress from self-weight, dead load, and live load and the tensile stress is resisted by the rebar.

The tool cut out the grout but it was very resistant, which I don't believe is very common.

I am not suggesting doing this for the roof but two ways to convert insoluble iron oxide( rust ) to a soluble form that is removed with a water rinse is to use either oxalic acid ( 5% solution on the rust for about 30 minutes( can wet towels so it adheres and does not run off) in water or a commercial product called "Iron Out" which is sodium hydrosulfide I think.

Persistence beats resistance every time.