When posting in offering threads you should: Avoid to troll and sig-spam like user killyou72 by posting garbage and repeatedly harassing the thread opener by making offers when the thread opener does not want to deal with you, because he does not deem you trustworthy.
You should also avoid posting garbage items for months and years on end, continuously bumping threads for items that are not only off topic but also something no one wants that simply just clog up a board.