Are charger that arent bought from Apple itself trustworthy / not going to damage my battery?

Here are some words of comfort for purchasing 'genuine' Apple chargers from non-Apple sources:

https://9to5mac.com/2016/10/19/amazon-fake-apple-chargers-cables/

http://www.zdnet.com/article/how-to-avoid-buying-counterfeit-apple-cables-and-ch argers/

The only non-Apple vendor (aside from Apple Authorized resellers) that sells genuine Apple chargers is OWC.

Ciao.

Depends. You can buy a used one on Craigslist, Amazon, or ebay, or somewhere else, that's a legitimate Apple one. However, there was recently some news about *fake* Apple products for sale (chargers and cables) that were causing issues with Apple equipment. You can also look for used real ones at your local authorized Apple reseller/repair shop. Best Buy might also carry some, but not sure as I don't generally shop there.

You are correct that real second hand Apple chargers can be purchased from a variety of sources. Does that minimize the risk of getting a fake is an open question.

Best Buy would be a safe bet since they are an Apple reseller and do have their own reputation to maintain. As I mentioned in my post, authorized Apple resellers also are a good source of getting a genuine charger. All other sources are suspect to varying degrees.

As the OP asks, why would some one offer a 'genuine' charger for 30£ when Apple charges 79£? I see a very large red flag with the 30£ option even though Apple has very large markups on the price of their products.

Ciao.

I agree with everything you wrote Ogelthorpe.

As for why someone would offer a 'genuine' Apple charger for far less than the price of new one from an Apple store, Apple website, or authorized reseller?

My guess is because it's either stolen, used, or a fake.

They are fakes, so damage to your Mac (or you) is quite possible.