Easiest and least expensive way is to minimize the number of valves and trim kits required to get the water to the supply heads.

I'd recommend looking at the Hansgrohe Thermobalance III. The valve itself will be around $75. they are getting a bit more difficult to find these days.

Then you'll need a trim kit for that specific valve. Trim kits can vary in price, but they are usually in the $250-$400 range. Remember, the trim kit has to fit the valve, so buy the valve and the related trim kit from the same source to minimize errors.

From there on out you can go with whatever manufacturer you want for your other pieces as long as the styles and finishes match the valve trim kit to your satisfaction.

For your "regular head" you'll need a shower arm and a shower head.

For your "rainhead" you'll need a shower arm and a rainshower head. I recommend 12" heads, 10" minimum.

For your handheld, you need a wall outlet, a hose, and a handheld head. If you want the height adjustable, you'll also need a wall bar that usually includes a sliding bracket that will hold the handheld. If you don't want adjustability you don't need the wall bar, just a wall bracket that fits your handheld.

For handhelds, it's usually best to buy a set that includes all the pieces...the wall outlet, the hose, the head, and the wall bar.

I recommend getting a hose long enough so the head can reach the remote corners of the shower for washing the walls down.

Additional info here.

Most valves have limitations or restrictions on how they port water, and the TBIII is no exception. So read the instructions prior to giving them to your installer.

With the TBIII, when you rotate the valve ON, water will come out of port #2 first. So it makes sense to plumb that to your primary shower head, the head you'll use most often.

The TBIII can also provide water to two valve outlets (and subsequently, two shower heads) at the same time. So figure out which two you think you'd like to have the option of running at the same time and plumb it accordingly.

Best of luck with your project.

Awesome that is just the info I am looking for!!! Are there other valves that do the same as the Hansgrohe in case I have trouble locating it?

So the valve and the trim kit would need to be handsgrohe, then I can build from there?

The valve will be the main issue. I'm not up on everything that is out there, but if you can't find a TBIII or another valve that can be plumbed to three heads, then yes, you'll be looking at a some other combination. The combinations can be mind-numbing.

You can have a supply valve (that sets temp and volume) that sends water to a diverter, and the diverter will send the water to your shower heads. That's an extra valve and an extra trim kit. Cha-ching.

Or you could go as far as to have a single supply valve for each head. Three valves and three trim kits. Cha-cha-ching.

Your second question...yes, a Delta valve needs a Delta trim kit. A Hansgrohe valve needs a Hansgrohe trim kit. The trim kit needs to be matched to the valve.

And just for further clarification (or confusion) Hansgrohe is going into the future with their "iBox" valves. The iBox is fairly versatile, it can be plumbed several ways. And depending on how you want it plumbed, you'll need a certain "model" or "version" (not just style) of trim kit to be able to operate the valve the way it's plumbed.

So if you think of the iBox valve as the main trunk of the tree, there are then 3 or 4 main branches or models of trim kits that will fit that valve. Then within each model, it branches out further into the various trim kit styles (traditional, modern, etc) and then even further as each style of trim kit can be had in various finishes (chrome, nickel, etc).

It sounds more complicated than it really it.

I had my plumber install Hansgrohe's iBox because, like you, I did not want 2 trim pieces on the wall. The valve will control the temperature, volume and the diverter. I added the Metris S trim piece along with the matching tub spout and I am doing a wallbar, handshower and water supply.

HTH

I had a similar question in another thread about Rohl. We went to Ferguson's last weekend. My husband wanted one Pressure Balance trim kit and valve and didn't want a separate diverter valve for the handheld...he says it is less to clean...not that he cleans the shower anyway :)

At the time we were looking at Newport Brass and the sales rep told him that we had to get a separate diverter valve and that the diverter valve on the PB trim kit was for tub only. She said they were all that way. Is that true? The Rohl shower package I am looking at seems contradict this.

How do you know when you need a separate diverter vs using the diverter integrated in the PB trim kit?

Brands I am looking at are Kohler, Newport Brass, Jado, Rohl and California Faucets.