Age doesn't matter unless you're planning on selling the car right after the repairs are completed. My daily driver is a rusty trusty '88 Grand Caravan because it has only one very reliable Engine Computer. All of my newer cars and minivans have numerous unreliable computers to do things that computers were never needed for before. If you like the car and plan on keeping it, what difference would it make if it's five years old or 20 years old?
If you're still undecided and can be without the car for a while, consider looking for a community college with an Automotive program. We were always looking for live work to give the kids real-life experience. We charged ten bucks per hour for what the job was listed to take, and parts at cost plus ten percent to form a "breakage fund" in case we damaged something, so taxpayers didn't have to pay for our mistakes. The drawback is engine work will only be done the one or two times per year that subject is being taught. Also, since the students spend part of the day in the classroom or other classes, they only get to work on the car a couple of hours per day. It will likely take weeks to get your car back.