Talk to your installer and if you can get another quote, please do so. As an installer, I find that the most important thing I try to hit is the client's budget. You can't beat around the bush with a target number and a good installer will talk to you about the options which go along with any budget.
I will say that I don't find their costs to be crazy, but you should check Amazon for some of your options for what may be available and compare pricing.
I often buy off Amazon, but then I will mark it up about 10% to my client's for the time and effort to get that stuff for them.
Certain things look pretty close, like the fiber-based active HDMI cable.
This is similar, and is $230. I can't tell if my pricing is AU$ or US$...https://www.amazon.com.au/RUIPRO-4K60HZ-HDMI2-0b-Supports-HDCP2-2/dp/B06XGDFCSC/ref=sr_1_1?keywords=hdmi%2Bcable%2B30ft%2Bfiber&qid=1557687826&s=gateway&sr=8-1&th=1
But, the short HDMI cable is crazy priced. It should be closer to $20 max for someone else to provide you a 2m or shorter 18Gb/s HDMI cable - and they should still make good profit on it.
The screen is worth looking at as well. If you have access to Silver Ticket screens (Amazon) or Elite SableFrame screens, those will perform well for the money and are likely a fair bit better on your budget.
The hard part in all of this is that I'm not aware of anyone who can put all this stuff in for you in 6 hours. Doing it myself would take 12-14 hours depending on how I needed to run the cabling. Certainly nothing in walls will happen in 6 hours.
I will say I think the projector mount specified is WAY overpriced. For that much money I would check eBay for a Chief RPMAU mount. I don't see that, but this one is STEAL at the price listed. Regardless of what projector you get, I would strongly recommend this if you can get it for under $100 down there.https://www.ebay.com.au/itm/Chief-RPA-Series-LCD-DLP-Ceiling-Mount/113704350452?hash=item1a794eb2f4:g:tWYAAOSwgaNcoeor
You may be just as happy with a Sony UHD Blu-ray Disc player vs. the really nice Panasonic. Check pricing.
The Marantz receiver is fine. If it doesn't match your budget, get a cheaper one. Maybe a Denon or Yamaha to get you going.
Speakers are a tough choice and you really should shop around for different models that you like. In-walls or little bookshelf models are nice. But slim floorstanding may be better. It depends on how much room you have and how good you want the sound. I think it's about a 50/50 measure of impact when you get good audio and pair it with good video. But, good speakers will last 30+ years. So, spending a LOT more on good speakers can be a lifetime purchase (not an investment, but a purchase). Especially the subwoofer. SVS is respected and the price is considered pretty solid for the quality. B&W I think is very respected, but a bit overpriced for what you get.
I'm assuming SPC14 is 14-gauge speaker wire. $80 for 100 feet (or so) is not a bad price. Though, once again, you should check pricing on Amazon.
Kinda like this...https://www.amazon.com.au/NavePoint-250ft-Audio-Speaker-Conductor/dp/B01ETLP48I/ref=sr_1_fkmrnull_2?keywords=speaker+cable+14+awg+250ft&qid=1557689111&s=gateway&sr=8-2-fkmrnull
So, not really overpriced there either.
I think if you aren't going to do it yourself, then this is not a bad proposal. A few things overpriced a bit, but not crazy.
If all wiring is in-wall, then that's a lot of work for almost no labor charge, so I think that's a really good deal on the labor.
- Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.