It depends. There are different levels of rust. Some of them are light and only on the surface, and can be fixed relatively cheap and rather quickly. Others are more intense and they span deeper into the surface. These can also be fixed but they might require you to spend a lot more.
If your car is plagued by extreme corrosion levels, then there is no logic in buying such a car. Even such levels of rust can be fixed but they might require you to completely disassemble the car, buy new panels or even manufacture them.
If you do want to buy a car that is corroded, you should take the car in for a comprehensive inspection just to make sure that the corrosion levels are not higher than what you might think initially as rust can form in places that are completely out of sight.
No matter the levels of rust, try to figure out if it makes any sense to buy a rusted car financially. Only a handful of extremely limited and valuable cars make sense if the levels of rust are extreme. If the levels of rust are mild and the price takes that into account, then it might make more sense.
Mild rust
Many cars are often plagued by mild levels of corrosion. These types of rust spots usually form behind the wheels and are commonly visible from the outside. Furthermore, undercarriage rust is also fairly common, but you need to inspect the car’s underside to see it.
These levels of rust are easily fixable if there is no need for any repaints or such. All you have to do is grind the surface out until there is no corrosion left, sand it smooth, prime the area, and later paint it with an automotive-grade paint.
If the rust is located on a painted panel, then you have to do all of the above, but paint the area with color-matched paint and a couple of layers of clear coat. All of these fixes are fairly easy and they are not time-consuming. It makes sense to fix such levels of rust, and especially so if the car’s purchase price is discounted.
But before you decide to buy the car, a thorough inspection is necessary as rust spots can hide in many areas that are not visible to the naked eye. If such levels of rust form on a new car that should offer factory rust protection, chances are that the car has already been fixed.
Moderate rust
Moderate levels of rust consist out of non-localized deep rust spots throughout the car. Such cars are often misused throughout their lifetime, and more often than not owners don’t really care about them all that much.
That should be a clear indication as to how the owner treated the car and trusting such an owner poses a great deal of questions. Even these levels of rust can be sorted out, but it takes a lot more time and effort to do so, especially if the rust has already penetrated the inner layers of the car’s components.
Fixing such levels of rust can even require you to replace a panel, use panel bonding or even weld a couple of panels. If the car is not structurally compromised, all the rust spots are located try to figure out the final value of the car after all these problems have eventually been sorted out.
Rarely are such levels of rust fixed, and it only makes sense to do so if the car in question is a limited edition, highly valuable car.
Extreme rust
Extreme levels of rust are rare and almost always not worth considering. These cars are structurally compromised as a bunch of the car’s integral panels such as the frame itself are corroded, and the car is not safe to drive or even be near it as it can break apart at any time.
It makes no sense to either fix or buy such a car. There are a couple of well-documented cases of so-called ‘’barn finds’’. A barn find is usually an extremely limited edition highly valuable car that has been forgotten for decades
Such cars are rusted and sometimes even unrecognizable, but they are fixed due to the sheer value of such cars. A great example of such a case is a 1960s Ferrari 250 GTO that has been buried in a man’s backyard for decades.
These 250s are worth tens of millions of dollars, and a 250 GTO in dreadful condition can still be priced a couple of million dollars. So yeah, if you do encounter one of these in your backyard and it’s not already yours, you should buy it.
FAQ Section
How can I protect a car from rust?
Firstly, you should wash the car regularly, park it in a garage and apply some form of paint protection film or ceramic shield if the car is of higher value. Undercoat the car with a special tar-based solution to further increase the protection levels.
You can also opt for various different kinds of waxes or sprays to further improve the levels of protection. Just take care of your car and inspect it from time to time for any signs of rust. Cars should be protected if they don’t offer any factory rust protection, so make sure you do your part.
Do newer cars need rust protection?
More often than not, newer cars are well protected straight from the factory and they don’t need any additional rust protection for a few decades after production. These cars use lots of galvanized steel in their construction, and they are further protected with lots of waxes and paint protection solutions.
Newer cars are also often protected by many different kinds of warranties that do cover rust. Only after a couple of decades and after the warranty has expired it makes sense to further protect these cars.
What is the best method of aftermarket rust protection?
The best method of aftermarket rust protection is probably a decently applied tar-based undercoat. These can last a few years if applied professionally and they usually cost $100-200. If you don’t want to use undercoating, opting for a dedicated oil spray is also an option.
These sprays are sprayed onto all the vulnerable areas, and they drip towards the nonreachable, but equally vulnerable areas. They also cost more or less the same, and they can last a couple of years. If you combine these two, you are probably safe from rust for a few years.