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10ft tall all down the driveway, so the potential new neighbors can't sit there and creep on me on their porch while i'm watering my plants in the drive, and as a bonus it'll keep their tree's stupid leaves in their yard where they belong
you can't even say i'm becoming a suburbanite, the town i live in is rural 
depends on your city/county about permitting and height restrictions (and setback/right of way from the road), but definitely get the property line demarcated first.
ive had cool neighbors that i didn't mind having a permeable border with and had complete weirdos who get drunk and stare without waving back, try to take and claim ownership of things, and let aggressive dogs run amok. or just invite a constant stream of new sus people over to be sus with. i don't have nice things, but ive had my place broken into by a neighbor's associate before and they seem to have gotten pretty frustrated that i didn't have nice things and took that out on the things i did have.
a nice privacy fence isn't going to stop you from being friends with a cool neighbor.
I mean it doesn't need to literally be 10ft lol
lol yeah it does.
i looked mine up when i lived in a relatively small and dense but relatively permissive municipality once. basically, for anything above 4' tall fence, the setback was pretty much the front line of the house structure. a 4' could be run to the right of way/sidewalk.
once you hit the house setback, you could do up to 8' or apply for a variance for up to 10'. 8' is intense to stand near IRL.
the bin laden compound had 14' perimeter walls, which was too high for parabolic mics and camera observation of the grounds from nearby trees... so 14' is what i consider The Gold Standard for Being Weird™
I think a 7-8 foot fence would work well enough for this specific case, it's just our main entrance is on the side of the house with a driveway running along it, and their front door and porch are like 20ft away. I think at that distance i'd feel obscured enough doing stuff in my driveway
I could also just get over my desire to not be perceived