Buying an acid right now is like trying to catch a falling knife you're going to get cut.

Roaches don't develop resistance to boric acid.

Then they stay put out of sight/mind away from kids or pets.There are some fairly safe dusts that are basically boric acid (Borax) and a sugar/flour mix.

Animal urine is a total pain to clean, and based off of my experience, if it is really bad, I want to let you know that I did several washings on the concrete with all sorts of different kinds of cleaners including muriatic acid.

That will be the acid test for them. 

If the copper makes you feel better then use it, plumbers in my area pipe their own houses in pex and only care for copper because they make more on material upcharge and labor to install.As a side note- acidic water breaks down copper, which ingesting can cause health issues, and can cause pinholes in copper piping.

Keep 2 plungers in the house, along with Liquid Fire or other acid drain opener.

This would probably be true if the vapor was truly just water, but the primary ingredients in e-juice are propylene glycol and vegetable glycerin, both of which are actually a very thin oil.  

The drano essensially is like an acid that can eat through the hair but with too much it may damage piping.

Steven Maduro, you can get rid of roaches permanently with "Roach Prufe", which is boric acid.