$15K could be a tight budget in most areas of the united states even if you act as the general contractor. $15K would be very limiting in Los Angeles (Brentwood), CA where I live. Many contractors here will not take on small budget projects. One key point that affects your project cost is your location. Labor and material costs vary from one locale to another. Fixture costs are more standardized across the nation. While you plan to use plumbing fixtures from Kohler and Grohe, you need to be more specific given their prices can vary depending on quality, style, etc. The biggest unknown about your project is what framing and/or preparation will be required to install the proper substrate (i.e., cement board vs. cement with wire mesh)to float your tile on the bathroom floor and in the shower, and any plumbing modifications that may need to happen to accommodate your new fixtures even if you do not plan to move them. Also, will the ceiling of the shower be tiled? What finishes do you plan for the bathroom walls and ceiling? What is the total length of your vanity? If you plan to pull permits, then you will need to make sure that you include the costs for any retrofitting that may need to be done to meet the current building code requirements. You also may want to make sure that the quality of the bathroom that you install is commensurate with your home's value and your neighborhood's socioeconomic standard. In conjunction with this consideration, you need to evaluate your long term plans --- Specifically, how long do you plan to live there? If you plan to live there a long time, I would avoid cutting corners. Select surfaces (i.e., Tile or Stone) that you can live with indefinitely. The cost of surface changes in a shower are particulary costly and basically require you to rip out the entire infrasture less the plumbing just to change the color. Plan for unexpected costs for which you cannot account until the demolition is done. For example, you will not know how the new shower fan can be vented until the shower ceiling is torn out.

There is no exhaust fan requirements. There may be "make up air requirements" if the laundry equipment is contained in an enclosed room with a door. You would have to allow for the dryer to pull air into said room in order to exhaust freely.

There can be so many electrical switches involved with a bathroom - overhead lights, sconce lights, shower lights, exhaust fan, toilet room exhaust fan, heating, etc. The list seems endless. I am trying to plot out the best, simplest layout for all out switches. I would really appreciate seeing how other people handled this part of the design. Did you divide up your switches into various spots in the bathroom or try to consolidate everything together? Did you utilize special timer switches or put exhausts on a sensor? Did you put your sconces and overheads on a single switch or separate them? Did you add anything outside your bathroom to turn on your bathroom heat in the morning BEFORE you enter the bathroom? Did you install any special dim lighting option for the toilet room at night? Any and all advice - AND PICTURES - welcome and appreciated!

Panasonic has some very nice heat/vent/fan units, but most will require a dedicated circuit because the heat capability draws about 1500 watts of power. Another option for venting two locations with one exterior vent is an inline fan in the vent to the roof, and a Y connection for the two vented areas. However, this is not a real common solution and I've mostly seen it used when someone does not like the noise of the vent fan in the room. Bruce