Bad traders

Usually a reminder or "no stress, just haven't received yet" is sufficient - often I feel an unwritten caveat as often cheap prices on here is that people posting stuff do so somewhat more at their convenience. Obviously completely taking the piss is no good - I purchased something and the guy said he'd send 3 days later and I hadn't heard anything for 10 days so a polite email with no response, then another a week later and another a week later (at this point I was thinking PayPal dispute though didn't communicate it in my msg). Anyway just over a month later bits turned up with extras and genuine apologies - all fine and glad I didn't get shitty! If it'd been much longer, after three well spaced polite messages, I'd have just started a PayPal dispute without notifying them I think.