7 days is most certainly not enough time to "slab a planet or two for yourself" unless you're just going for the garbage planets. (Moons, asteroids, etc)
Find system, fly to planet - minimum 30 minutes in system
Fly down, then down, - 2 hours
Place slab - 1 hours
Cross terrain - minimum 30 minutes
Place slab - 1 hour
Cross city - 21 minutes
Cross terrain - 30 minutes
It takes minimum 2 hours to lay a slab and get to the next location. So, minimum 24 hours for 12 slabs. 12 x 7 = 84 = (1) 9x9 you can handle by yourself....if you don't sleep...or go out...or do anything besides swc that can't be broken into your increments.
And that's if you know what you're doing and have the funds to do it. 9x9, minimum 1.5m each = 121.5m
You can probably cut corners a bit here and there (lay slab and cross city at same time,) but I wouldn't ever chance finding and trying to secure a system on my own.
It's been done before, sure...I just did a 4x4 only system by myself, but the vast majority of systems aren't like that. Look at Boonta, for instance.
Scouting is a team effort. Don't advocate this "you can do it yourself" approach, especially if you've never done it before.