No trench drain at the rear? No capillary break? No wetroom waterproofing of the whole chamber? https://www.ceramictilefoundation.org/homeowners-guide-to-hiring-qualified-tile-installer

We generally prefer historical cost basis over any time of assessment, so what you paid for an item. However, one problem with the historical cost basis for ad valorem taxes is it adjusts for realized gains and losses while not adjusting for holding gains and losses. This means that two identical houses would pay two different taxes based on the last time they were sold. This isn't quite fair so to remedy this, ad valorem taxes are occasionally adjusted to compensate somewhat for holding gains and losses. In other words, we don't want people who bought 3 acres next to Central Park 65 years ago, to be paying property taxes on $100,000 when an identical property next door pays taxes on $15,000,000. That is the entire purpose of adjusting property values. Improvements aren't simply holding gains, it is putting money into the structure so that it is nicer. If you want to fairly tax improvements you would need a tax on the increased value less a tax credit the amount paid over the marginal assessment value. So, the premise that you have some moral obligation to pay marginally higher taxes because you spent $50,000 for a nicer kitchen that adds only $20,000 to the property value, is one I find questionable. In other words, if you paid more for the remodel than it added in property value you should get a tax credit against the increase. However, that is far too complicated and thus taxing jurisdictions who are acting efficiently and attempting to be fair, avoid increasing valuation for improvements and replacements, but do increase valuation for additions. Now this is completely different than rules that allow select groups to avoid assessment for holding gains and losses.

Thanks everyone for your comments! Not only is the bathroom no longer a dark hole, but even the back of the house/bedrooms feel lighter because of light emitted when you walk past it! It was certainly educational, my hat is off to everyone who undertakes this endeavor.

@Z Y the white tiles are from lowes in two different sizes, they're called satorini white glossy tile. The center accent tile is from home depot: https://www.homedepot.com/p/Ivy-Hill-Tile-Pacif-White-Shells-11-81-in-x-11-81-in-x-2-mm-Pearl-Shell-Mosaic-Tile-EXT3RD102059/300915818 i got the cabinets custom made.. which really wasnt that expensive considering...