Have a shower stall that is tiled. One wall has damage at the bottom. Tiles have leaked over time and the sheet rock is gone. Needs to be replaced. New sheet rock, retile, new grout. What would be a fair price to charge on a job such as this?

Depends on a few factors. 1 are you supplying materials and labour. Is the foor mortar or a basin? Mortar might be weakened from water. How big is the repair area. Charge by the hr. if you are not sure what exactly you are getting into. Let me know.

I will supply all materials. The floor is mortar. The area of repair is about 4' wide. What is a fair price to charge by the hour? Thank you for your help

If you are a contractor I would be in the 25-50 dollar an hr. if you are a dyi charge what you think is fair. You are probably looking at a three to four hr repair and maybe 2 different days. One for thinset and the other to re-grout. Good luck

Well I think I would at lest double razor96's estimate on time and I am terrible about underestimating the time required. I do quite a bit of this type of work. You said that the damage area is about 4' wide, you didn't say how high. It is probably further than you think. Since you will be pulling out damage material slowly to find the extend of damage it will take a little time. Then you may find damage to the studs. After that there is clean up time before you begin rebuilding. In replacing the walls you should use cement board (Druarock or Wonderboard) in case there is a leak later on and you get a call back. Next of course is the replacing the tiles. I assume that you are not a tile setter so you will not be proficient time wise. In such situations I like to retile from the top down. That way I don't end up needing another 1/16" to get the last row of tiles in between the old and the new. Filing down tiles takes a lot of time. I set a tile, then tape it to the tile above with masking or with strip of duct tape to keep it from sliding down until the thin set or glue grabs. Easy to do but takes time. That lets you cut the last row of tiles if necessary , the cut being hidden by the caulking at the floor. After setting is grouting, meaning another trip. After thinking about it I think I would say a day and a half minimum.

As far as how much to charge, how little are you willing to do it far. Then how much do you think the customer would be willing to pay. Labor rates vary too greatly for someone in another area to advise.

You didn't state if you will be using old tiles or new. If the cust has old clean tiles and enough to complete the job that is great. Chances are they do not and if you can not find new tiles that the customer will accept (They may not match very well) then you have a lot of cleaning to do on the old tiles all of the grout and most if not all of the mastic or thinset. This takes a lot of time trust me..
That said hkstroud made a lot of good points.