As for laptop charging, there can be one caused which is the current surge which spoilt the charger. This current surge normally originates from the power source. When u plug in to the charger, current surge will spoilt the charger and the charger cannot be used anymore. Slow charging or power cannot be charged usually associated with the charger connector. same thing can happen to handphone and other electronic gadgets. Usually the gadgets have issues for quite some time already. It does not happen overnite.

Since the verbal agreement is between seller and buyer, we cant comment on this part who is right and who is wrong. By right, it is the responsibility of the seller to provide at least personal warranty for electronic gadgets. Buyer as the consumer has the right to receive the item in perfect condition. By stating this, i am not saying that seller selling faulty parts, but it is best that seller help his/her customer to solve the technical issues. It is best to settle with mutual agreement, both party bear the repair costs together (just a mere suggestion).
And to buyer, it is ethically not right to just go every of his thread to state that he is selling 'faulty' items. To call him 'cheater' n 'liar' is just a bit too extreme. I just hope that this thing can be solved amicably. It is very sad to see a reputable seller being accused and a nice/serious buyer getting a faulty items. A perfect business deal that turned sour is the least we hope to see in LYN.