I am one of those crazy people who wants 2 of a couple different breeds ..... Is it ok to keep chicks I order in one area (indoors) until they are old enough to be in the coop (out doors)?
I am thinking about getting 2 silkies, 2 olive eggers, 2 easter eggers.. Small flock, all hens (hopefully). If I get any roosters, they will be dinner (sorry if that sounds mean, but roosters are not legal in my area).
If they are different ages is that ok? Should I quarantine each set of chicks first before introduction?
They will likely be all from the same local breeder.
Is it better to start off with eggs and hatch myself? or order week old chicks? I am totally new to all this, I doubt I'd be very successful hatching eggs as a newbie... It is also important to be that the hens all be kid friendly. So they will be handled asap.
At what age can chicks go outside in the coop safely? I will be starting my flock in Spring 2017. temp outside will typically be between 15-20ish degrees Celsius in the Spring.

Mixed flocks are wonderful. I've never had a silkie, so don't know how well they blend in with a flock of LF birds. I strongly suggest that you get all of your birds from the same place and at the same age and at the same time. Mixing and matching from different sources and different ages brings a whole set of issues that are difficult for a newbie to manage. Not to mention biosecurity issues. Sounds like you will be getting straight run. If you want to end up with 6 pullets, better get 12 chicks and have an exit plan in place for the roos. Hatching your own eggs, even for a first timer is not an unreasonable plan. But, it takes dedication, and there is a learning curve. If you choose to go this route, I recommend that you have a mentor to help you along. I started my first flock (this time around) with chicks hatched in a home made incubator. I hatched 5/6 eggs from a local flock, and added 3 EE to them from a local feed store. You might even consider going the incubator route and getting some local mutt eggs. Re: the silkies: your kids will be in love with what ever birds you end up with. Do you want small eggs? Do you want birds that are broody VERY often? Broody hens don't lay eggs, but they are often cranky and keep the nest box tied up for weeks at a time, unless you have a broody breaker pen.
How big a coop? MINIMUM recommendation is 4 s.f. in the coop and 10 s.f. in the run per bird. Any less than that, and you invite issues with aggression, feather picking, disease. If you intend to occasionally add to your flock so that you are not running a nursing home for geriatric hens 3 years from now, you might want to build with that in consideration. If you intend to ever let a broody hen set on eggs, again, you'll need more room.
Coop safety: Chicken wire will only keep birds in, will not keep predators out. Build with that thought in mind. Lots of ventilation is a MUST, no matter what climate you live in.
Kudos to you for thinking this through, and doing some planning before bringing home some fuzz butts!