When trying to do automotive repairs yourself, there may be times when you do not have the right equipment or experience to properly diagnose a problem. Some times even the professional certified mechanics might have difficulty. This is when you must simply replace a suspected faulty part and hope that it fixes your problem. When going this route, you can save a lot of money by purchasing 2nd hand car parts rather than opting for brand new ones.
There are often many junk yards in any town that will offer "you pull it" service. This means you can get a better price on 2nd hand car parts if you bring your own tools and remove the part yourself. You will also have a better chance to inspect and decide whether or not the part is in good enough condition for your use.
Other junk yards will hire special staff to pull all road worthy parts from a totaled vehicle and put them up for sale. Buying 2nd hand car parts from places like these will often have some sort of guarantee on all parts other than electronics. This is because electronic 2nd hand car parts can sometimes be damaged simply by hooking up to a faulty electrical system, and there is no way to determine who is at fault. Those junk yards will however have a process for determining quality control so you can shop with comfort.
This can save you a lot of money when you are not sure exactly what is wrong with your car. Generally there will be several parts that you know could be causing the problem, so you will have to start with one.
Cheap used car parts may have slightly less life left in them, but will be much easier to fit in your budget. You never know just how much is broken until you try and fix it. You won't know if a bolt is stripped until you try and remove it. Just be sure to carefully look over your 2nd hand car parts so that you know you are getting a working piece.