From memory, the total cost was $2,006. However, I had to buy about $40 worth of stuff to complete it. I ran out of the special central vac tubing (schedule 20, I think), and had to improvise/adapt/overcome to make standard schedule 40 work, of which I needed about 40 feet. The walls of schedule 40 are thicker, so it isn't any good for the hide-a-hose system, but it works fine with the vac pans. The OD of schedule 40 is a little different also. The trick was (pause for dramatic effect...)
Fernco boots. They just barely fit over the vacpan outlet, and then connect schedule 40 to the central vac tubing, which has a slightly different OD. I used 45 degree connectors with about a 10" piece of pipe between them, as I wasn't happy with even a long sweep elbow. Where they needed to be is NOT easily accessible in the finished construction, so I wanted to make sure nothing would get stuck there. It's only used in the kitchen vac pan. I opted for 1-1/2 schedule 40 rather than 1-3/4 (or was it 1-3/4 instead of 2" I don't recall), because I wanted more air velocity rather than air volume. I chose to adapt down in ID rather than adapt up. It was a thought out tradeoff. Whatever we suck up in the kitchen will probably be pretty small but possibly heavy. If it will fit through the opening of the vac pan, it will fit through the tubing, and the moving air will have the velocity to pull it through the tubing. In an extreme example, if I went with say, 4", I'd have a lot of air volume, but not enough velocity to pull a pile of sand through the tube. The larger the tubing, the less efficient the system overall. Even as it is, I have to wait a few seconds for the central unit to pull decent vacuum before sweeping anything into the vac pan.
Going back to the cost, I opted for the filtered cyclonic collector unit thing rather than true cycle or a standard filter bag unit. The bag unit was out because bags are stupid and can plug up pretty easily, then need replacing. The filter is reusable. I can easily recover stuff I accidentally suck up from the canister. The true cyclonic had to be vented outside, which I just didn't want to do. If I want to, I can vent the one I got outside and it would be even quieter. Not that it would matter, as it will be in a garage separated from the house by a 2x6 wall with R30 foam insulation. The collector was like $800 or something like that. Tubing was a fuzz over $1 per foot. Vac pans with installation kits were maybe $40 each. The 2 valve hide-a-hose option was $850. Accessories were like $200. I probably didn't need the vac pan installation kits, but they were only like $7 each, and I mayhave used a fitting or two. I'll probably regret not doing more vac pans, but I really don't have anywhere else right now I can think to put one that's easy to do. Besides, the only other place I can think of (basement slider) is small, and the more tubing I run, the less efficient the system becomes. It would also be hard to run tubing perpendicular to the joists. Ideally, the one in the kitchen would be installed under a toe kick in the island, but that's kind of hard for me to do since there's no island there yet and ai wanted to get the system buttoned up now. I'd rather not have tubing just floating there until then. It might be easier to get to it with a broom if it's flush with a wall flanked by thin trim rather than tucked under a toe kick, anyways.
Today I finished the system as far as I can really go with it. I wired each outlet with the low voltage control wire, and secured it as needed. The vac pans are just kind of chilling there, as I really can't mount them until the floor is finished. They need to sit directly on top of the floor's surface. I'll have them install faux cold air return grates on the back sides of the walls where the vac pans will be mounted so they'll be easy to service later if needed. I didn't secure the tubing within 3 or 4 feet of the elbow above the vac pans, so they can float upward a couple inches as needed. I'll aslo remove the hide-a-hoses and outlets after our builder gets the chance to play with the system a little. He's not familiar with the hide-a-hose sytem and wants to see it in action. I'll take off the outlets and install the blank plates until drywall is complete. Oh yeah... I need a couple more nail guards. I got most of them covered, but I don't like the crappy puney little ones I got at menards. I also removed the central unit from the wall in the garage and locked it up in the barn for anti-theft reasons - garage doors aren't on yet and it's visible from the street.
One last edit - The company I got the system from has a flat non-flexible rate of $900 to install it. Doesn't matter if it's new construction or a retrofit. Had this not been a new construction application, I think I would have just paid the $900 and would have been smiling the whole time they were there, clamoring through the attic and guessing where plumbing/electrical/ductwork is. And the finished interior walls will be filled with fibergalss insulation for sound deadening. Good luck running 2" tubing through that.