Thank you all for the informative posts! I think we may need to go "back to the drawing board" and re-think our plan…… Our current home is a fairly well built 20 yr old "spec" home in Boise, Idaho. I think the first thing we need to do is find out what the underlayment or decking is, and if it is substantial enough as-is, or if it will need to be changed. I can see this spiraling out of control quickly! What I had in mind (and I probably used the wrong term) was a pre-fab shower base, which we would have installed by a plumber. My husband would then install the proper cement board and tile the walls. We have had a shower like this in a previous home--although it was a smaller shower, so flexing might not have been much of an issue. We are trying to be budget conscious and also simplify the installation procedure. But we certainly won't take any shortcuts that could lead to issues later. And--the information about "the weight of an average North American user" made me smile!! Thanks again--I'm sure I'll be back with more questions!

I m a little confused by the description of what each guy is doing. Whatever they do, make sure the floor membrane itself is sloped to the drain. Iy's a code violation to install the membrane flat on teh subfloor with sloped mud on yop of it. "One mud floats the entire shower after pan and cement board are installed." Is this guy floating mud directly on the cement board? Floated walls are typically (at least in my experience) tar paper and then expanded diamond mesh on the walls, with the mesh wrapped through the corners. Then the walls get floated with mud. A tile backing surface like that with mesh wrapped through the corners will not crack on the wall-to-wall corners, so the corners can be grouted. If you're looking to avoid corner cracks, you'll have better success with a fully floated shower that has mesh wrapped through all corners, versus tiling over a lightweight tile backer board like cement board. I do like Shluter's Kerdi membrane, as well as other surface-applied membranes. They can be installed over cement board, and even over a floated mud wall. I think every tiler should want to control the process from studs-to-tile. The tile can only be as good as what it goes over.

I installed my solid surface shower walls over drywall, not even greenboard, and put the custom solid surface pan over the wood subfloor. If you leave an 1/8" between wall corners and pump them full of color matched silicone, it allows for panel movement without leaking. Another of the advantages of solid surface in the shower, besides lack of grout to maintain, is the labor and material savings of waterproofing. Plus the foolproofery.

I think we are drifting from my original question of what a pan would cost if a pro would price it out. I understand no pro is going to want to come in and do just the pan. I happened to find a pro who works for a company that does this amongst other things. I get it, I was a caulker in a previous life and our owner never wanted side work being done but in the same breath also said that they couldn't do all the work out there as we didn't have enough employees or the margins weren't worth doing. So, yes, I have a guy who does this for a living willing to come in and pour the pan after hours/weekends and basically leave me with applying the Redgard and finishing the bathroom remodel I have already started. My plan was if his price didn't jive with what others on here were saying, I would audible and go with a Wedi or Schluter pan and keep moving forward. This would delay the project somewhat as I would have to learn how to do this style pan but I would get it done. I also understand no project goes as planned, there are always the things that change "all you have to do plan...". I've already had these with the project such as having to cutout the 10' vertical cast iron sewage pipe and pull it up from the basement and into the bathroom as the 90 degree elbow was rotted out on the top or the framing behind the linen closet wall (which will become part of the new shower) not being plume and spaced properly for CB to hang on. All I want the guy to do is the shower pan, I will deal with any other issues that arise. I'm not looking for a warranty, you always take a leap of faith with a 'side jobber'. If for some reason something isn't right for him to do his pan, I would either fix it or pay him to make it so he can move forward. I just was hoping for some pros to enlighten me on what a shower pan cost would be if they itemized their project. If this is something that is frowned upon, than I understand and will be back on the forum for more project-related questions. Thanks everyone.