If there is no flowing water you could scrape, acid etch, and throw drylok on there for $100 in materials - easy DIY job.Note: you do have electric and plumbing there that need to be moved for proper sealing,  so you would want to have pros handle those pieces.

I remember in New Delhi they has sponges on sticks soaking, between wipes, in a bucket of what smelt like acetic acid. 

Sun hits the panels, glycol gets hot and goes to a storage tank inside, then into the radiant floors.

Remember inflation is like acid slowly eating away at cash making it a little less every day, so it must be actively deployed to preserve itself, via equitable gains safeguards and keeps it working 24-7 as a perfect hedge against inflation. 

If you have a pile of lead acid batteries than need maintained and replaced regularly it will be a harder sell.

Clean again to wipe off dust.I used "Zinsser Cover-Stain" primer; this stuff is thick and smells like battery acid.

It's water based and is not quite as impressive as the acid stain method.

@Mike Franco also consider acid stained concrete for durability

The tub guy gave us a little bit of a hard time since all the acid would run down into the basement (no drain hooked up)— we created a makeshift funnel for the acid to funnel into a container so we could get the job done right.

Works well if installed properly.I had a property with pex and either because they were not crimped properly or for whatever reason, there would be a slow leak and the slightly acidic water (well) would eat away at the fittings, causing many leaks and replacements.