You haven't really said anything we can use to judge dollar amounts, but you can run into the same costs with any car. Some people bail out of a car that has had multiple, but different problems, then the next person who buys it drives it for years with just regular maintenance. Some people trade off a car at the first sign that a problem might turn serious, and end up with one that's much worse. This is why I'm happy to not be a salesman. They get blamed if you end up with a car that costs a lot in repairs, regardless if they talked you into trading for a newer one or keeping your old one and spending the money in their repair shop.
A squealing belt is hardly a reason to trade a car or be afraid to drive it, especially when 99 percent of the causes are easily fixed. Wrenchtech mentioned the harmonic balancer, (aka vibration damper). That is usually relatively rare, but while it is probably the most expensive cause of a squeal, it is hardly a reason to get rid of the car unless you expect to start having more problems in the near future.
Normally I'd suggest getting a used balancer from a salvage yard, but if this is a somewhat common problem on this engine, I suspect a new one with a warranty and labor would be less than around 300 bucks. A lot of people spend more than twice that amount twice a year for one repair after another.
As far as being safe to drive, that depends on your tolerance and what you're willing to put up with. To me, the least trustworthy car is a new one that has no track record and no history. My cousin has a GM truck that developed its first small problem at 80,000 miles. A neighbor needed a new engine in his two year-old GM truck. My daily driver Grand Caravan is so rusty, the carpet is what's holding the front and rear together. THAT, to most people, is unsafe, but it keeps going and going. I have a newer Grand Caravan that I won't drive any further than I'm willing to walk back home. It has never let me sit or needed more than new tires, but I don't trust it, so is it "safe" or not?
I went on a road trip three days ago with a friend of my mother's, and she almost had a mental meltdown because I let the gas get down to a quarter tank. I often carry a can of gas with me because I zip past all the other gas stations and try to make it to the cheapest one 30 miles away. I run out on the side of the road about two times a year, but only when I'm alone. We took her car on that trip. It's a late '90s Buick, ran perfectly fine, is comfortable and quiet, but now she's all upset because in the middle of winter, the windows fogged up a little. I tried to explain that she never gets it out of the city, and never gets it warmed up, but she's obsessing about trading it in. I tried, but I couldn't pound any logic into her head.
Another neighbor just traded a two-year-old Ford after its third very expensive electrical repair, which is all too common. So far, their new 2014 Explorer has needed to have two computers replaced in the first four months. They haven't stopped to think what that would have cost them if it wasn't in warranty, and what it's going to cost them in future years.
My point is there's a wide range of what can be considered "safe", and until you can tell me otherwise, what you've described so far is something that needs a live person to look at so you can make an informed decision. We deal with belt squeals all the time. They've become common on all car brands since the 1980s when they started using the current "serpentine" belt design.
Sorry for rambling on. The water test I mentioned is just to prove whether or not the noise is indeed related to the belt. If water causes a change in the noise, it's something to do with the belt. It's more involved, but you can also remove the belt, then run the engine long enough to see if the noise is gone. That will tell you if you have to look someplace else, or if the belt tensioner and pulleys are involved.
Thursday, January 15th, 2015 AT 4:05 PM