DIY is very rewarding. Not only do you save money but you also learn a lot about your car (and cars in general). As long as you take your time to research and prepare, and then take your time when you are installing parts, you will be totally fine. Not to mention since its your car you know that you did everything right instead of half-assing it.
Plus with as many members as we have on this forum I'm sure if you need it there is someone nearby willing to help you out! And there are tons of helpful DIY guides here on the forum.