18.5% price increase in one fell swoop, wow. Any more increases on the horizon?

More like 37% price increase for resin replacement, not cost effective. I got 15 vehicle washes per resin replacement, equates to about 10 dollars per wash. I parked my, no longer in use! :-(

Is this a duo bed or mixed bed deionizer? If duo bed, strong base or weak base?

It is a duo bed and the base is really strong. They have super customer service and are always a call away for questions and answers. You'll love it. Best investment we've made in a long time.

I don't have sediment issues in my home, just very hard water... do I need to install any type of sediment filtration in front?

You will not need a sediment filter in front of the SimpleChuck. This will fix your hard water by chemically stripping the water of the junk that makes you have water spots!

How many cubic feet of resin refill does the Simple Chuck hold when its time to refil?

I apologize for showing you a video, opposed to answering your question, with regards to specs…….HOWEVER, MAGNETIC BLACK METALLIC is the Paint Color on our 2019 Nissan Murano yesterday, and it was 88* when I did so. Sooo, my answer to your question is, IT IS WORTH EVERY WASH I GET FROM IT. BECAUSE I HAVE NEVER NOT HAD SPOTS AFTER WASHING ANY VEHICLE, EVEN IN THE SHADE OR EVENING! I have this Murano and a Nissan Titan, and now have washed them both a total of 9 RINSE CYCLES! The key, but a DUAL SPLITTER, AND RUN TWO HOSES……THE ONE FROM THE FAUCET, THAT IS YOUR PREP RINSE AND THEN WASH, AND RINSE WITH SIMPLE CHUCK, AND YOUR RINSE CYCLES WILL INCREASE! I HIGHLY RECOMMEND!!! Also, I apologize for those that don’t like CAPS, but those emphasize strong points I feel are important!