I have to disagree with some of your advice.
If your municipality lets you, install a septic instead of connecting to city sewer. No sewer fee. (Just get it pumped every few years).
You first tell him to minimize maintenance, and then you tell him to opt for something which requires more maintenance and is problem-prone. This makes no sense at all. Of course, some of this depends on location, but in most places I've seen, there's no sewer fee, there's only a water fee. The sewer cost is built in, and handled by the same entity, so there's no advantage in not having sewer service. Sewer service is simple and reliable; most people never have any problems (except maybe clogs, but you'd have those with septic too). Getting a septic tank cleaned is a pain, and worst of all, having a septic system means having a septic field, which can have problems, especially if there's any flooding. Finally, most places probably don't want you to have septic because they want the water back, so it can be processed and put back into the system.
Pick some trees and maybe bushes you like and put them in. Trimming every 1-10 years is easier than cutting the lawn every 3 weeks.
Bushes usually require trimming far more often than that. But avoiding lawns is a good idea if you can do it. Look up "xeriscaping". If you're going to have any lawn, try to keep the grassy area small, and use a manual reel mower to cut it; you'll get better exercise that way and generate no pollution. Use a battery-powered or corded electric weedwacker for edging/trimming. Have more wooded area, and a compost pile for kitchen waste, if you have the acreage.
Include low-voltage wiring for speakers as well as the alarm system.
This isn't 1995; why would you need wiring for speakers? That's what Ethernet, WiFi, and Bluetooth are for. Direct wiring to speakers is mostly obsolete now (it still probably makes sense for a good stereo system, but I'm talking about situations where the speakers are remote, and not really meant for premium sound quality).