I'm doing the encapsulation thing right now on a 100 year old crawl space. Found a pretty good deal on rubber stall mat to put down first. Then covering with StegoCrawl thick white plastic to control humidity from the ground. For the stand up area with foot traffic, I found some race-deck type...
I just finished a wall using GeoStone. Highly recommend GeoStone if you can get it. Whatever you use, make sure you buy more than enough so that the color is consistent for whole project. Work hard on the base so that first course is completely level. After that it's just a matter of stacking on...
I found one on fbmarketplace for $75 to do a bathroom remodel. Used it a couple times since. I'm 63 and it was a bit of a workout but very doable. Have your son on standby. I love pex A.
Mine has saved me several times. Uprighted a rental mini-ex that I layed on it's side. Pulled my tractor out of sticky situations a couple times. I believe it's paid for itself now.
I bought this exact tool off marketplace for $75 to plumb a bathroom remodel. Worked great and will use on future projects. Wouldn't want to make a living with it.