Yes that is a great setup as you are able to get down into the pores of the grout with the water/psi and flush it out and into the ninja. Remember the ninja only has an 11 gallon recovery tank so you’ll indeed be using the auto fill and auto dump features of the machine. Very cool be able to do continual work without having to stop and dump recovered water/chems and fill up clean water tank. Make sure you get 100ft of hose if you plan on doing residential work and include the amount of time it takes to set up and break down the equipment in your bid. This isn’t like a truck mount where you can just fire it up and go, you must unload and set all of the hoses and everything with this. Good to see this system added.
I would set up the system in the customer’s garage just outside the door leading into the house. This way you can plug into the 220v that the dryer plugs into, so that you don’t trip breakers. I’d also suggest plugging your fresh water hose into the hose bib outside and not to the adapter inside the home. If something happens to that connection while you’re cleaning and you don’t know if for a while then that mess is on your dime. I’m not sure if the HB cleaning solution is an alkaline or an acid but if it’s the later then do wear a mask. You do not want to be breathing in acid that has been atomized into the air. Unlike carpet you DO NOT want to work from the back of the house to the front. You want to work just the opposite. You don’t want to be dragging your hoses through chemicals. This could then get on the carpet if you’re not careful or just break the plastic hose down faster.