Did your old mechanic actually inspect the car? If not, it may not need some of the parts. The struts and/or tie rods sound more likely, but without a look and shake, who knows. If it drives straight, save up for the fix if it's a big number.

I'm with BB on the timing belt. Volvo Cars recommends changing the belt based on either mileage or date in-service. In your case it's 70k miles or 15 years. The rubber can become brittle and brake, as it ages. Do that first. They also change the tensioner and roller guides. Because its time consuming to remove these parts, they may suggest a water pump, since that's how to get it out when time comes.

Do the timing belt first thing. That's the most important problem. Here is a link to read.

www.swedespeed.com/threads/s70-and-850-timing-belt-failure.33785/

The S70 is a great car. These repairs are normal wear and tear items. You can easily drive this car forever, if routine maintenance is followed. Remember its cheaper than a new one and more fun to drive. The S70 is like a time machine. Enjoy!