Waterdrop G3P600 Reverse Osmosis System, 8 Stage Tankless Reverse Osmosis Water Filter, NSF/ANSI 42 & 53 & 58 & 372 Certified, Under Sink RO System, 2:1 Pure to Drain, Smart LED Faucet

https://a.co/d/064ZBlGs Waterdrop is awesome! Love mine and easy to install yourself! No pressure tank either

https://a.co/d/00MLFjJt I cannot recommend this product and company enough

What about under-sink options like this? I'm aware that I'd need to some (seemingly minor) installation, but if this allows me to get closer to what I want, I could try setting it up and then just taking it down before I move. Also, I have very hard/harsh water, will this mess up a RO filter? I plan on getting my water tested via ETR labs and I'm waiting on the kit. Then I could see what's in my water. I do know my water generally tastes awful without any type of filter.