1) The plumbers vinyl can be purchased at Home Depot or Lowes (got mine at Lowes) Some call it shower stall vinyl or plumbers vinyl. It comes in a big roll 4' wide where you buy it by the foot or in my case, because that was empty, a pre-cut size of 5' x 6' that you cut to your own size - that was $24 - it is 40 mil thick very pliable soft vinyl light gray in color. Thanks CarlD for the suggestion - that stuff is just the ticket for under steps!

2) My steps have flow throw holes all over the entire thing. The ropes will attached to the bleach jugs and run up through holes to the top near the top step so we can just pop open that step lid and pull out OR just get the steps tipped forward and pull out from behind - we haven't decided which we want to do yet as we didn't put them in yet.