Countertop reverse osmosis filters with remineralization are a viable option for renters.

“Use a reverse osmosis filter and remmineralize it. So probably better than even drinking bottled water is just remmineralizing reverse osmosis water in your home.”

“many reverse osmosis systems now come with a remineralization filter option that can add back these essential minerals and Trace elements back to the water after they're purified Alternatively there's high quality mineral drops that can be added back to the filtered water or people can just supplement with mineral supplements”