Ok thx Jim for this input....
Why dont you price out a diy shower and actually add something to this conversation?
Afterwards we can discuss your arrival at such number $
This is fairly easy...subtract your labor costs from your total costs, and what's left is basically materials. While it is not unreasonable for a DIY'er to want to 'pay' himself for the labor, unless he's taking time out of a paying job to perform the work, it is basically free to him. For those that can easily make more working, it makes perfect sense to pay a pro to do it, as it does if you want it done faster, since a DIY'er may only be able to work weekends or take vacation to do the job.
The costs of the finishing materials (primarily the tile) can vary hugely, sometimes by an order of magnitude or more. Selecting a linear drain adds potentially many hundreds of dollars to the materials costs verses a conventional or bonded membrane drain; so, the best comparison is of basic prep up to the point where it is ready to tile, and for the typical DIY'er verses a professional, the labor could double the costs. Again, putting the tile on the area, labor could double the costs.
If you really want to add up stuff like cbu, fasteners, membranes, drains, etc...the pro may get a discount from his supplier, and be able to get them cheaper, but he'll typically charge closer to retail for them to the customer (some markup is easily justified), so the actual costs to the end user may not differ much. I won't be home until the weekend, so probably won't tally up a parts list until then, but it really isn't necessary. The major differentiator between a DIY'er shower and one built by a pro is the labor costs. A DIY'er may end up spending the same amount, but he may use that extra to buy nicer tile or trim or accessories, or he may just produce the whole thing for a lower overall cost. Given some guidance, many DIY'ers can produce fantastic results, and I've seen a lot of 'pro' (as in paying someone to do it) built showers that were just a disaster waiting to happen. There are some real pros out there, there are a lot of 'pros' that don't deserve that name.