1. What color is your car? It looks DCM, and I'm not even sure THAT is base clear. Find out if it's a tri-coat because of the metallic.
2. It all depends on how anal retentive you are. You obviously don't want to open the door on a DCM car and see a bunch of white, so you want it to be color matched to a point. That point is directly proportional to how forgiving you're going to be with your own work. If you'll hate anything that's less than perfect, you may take a little longer or want to farm it out. For a daily driver, I'd recommend the mindset be somewhere between whether or not your wife would notice enough to bring it up and you wanting to show off the door jams to friends of friends.
For me, I'd pick somewhere insignificant and at least TRY something like a duplicolor paint code matched touch up can. You may be surprised on how close it actually is, and it'd probably be close enough for jams and underhoods, etc.