Some vehicle manufacturers sell their own budget brands to help you save money on repairs, while an independent garage will be happy to find you the cheapest component that will function as well as the original.
Stuart James at the Independent Garage Association advocates against going it alone on parts sourcing.
I would strongly advise the consumer to find a reputable garage and let the garage source the part for them, he says. This is the best way to be sure that a) the part will fit; and b) it wont invalidate the warranty.
If you do decide to source your own parts, your best bet is to visit your local retailer where you can get good over-the-counter advice. Although the internet can be a tempting place to pick up bargains, its also fraught with risk because you cant always see who youre buying from, and its difficult to judge the authenticity of a part you cant see in the metal.
The general rule for sourcing parts online, therefore, is buyer beware. That said, legitimate companies such as BMW are now operating their own parts stores on Ebay, selling original equipment parts direct to consumers.
Before you do anything, check the firm youre dealing with is a registered company, with a listed address and phone number. When the part arrives, check the packaging is properly sealed and hasnt been tampered with. Be wary of packaging that looks flimsy, and make sure that the manufacturers logo is printed correctly. Spelling mistakes and graphical errors can be a sign that the part is counterfeit and possibly dangerous.