If you use LQQK in any ad you post, you are spamming
This is something spammy people do. And it's annoying.
Craigslist morons will purposely misspell LOOK as LQQK for the reason that a lot of people will use the search operator -look in order to not see that word in titles when searching CL.
And yes, LQQK also happens on eBay. A lot.
Does it also happen on Amazon? Yes, it does.
Don't use LQQK when you post an ad to sell a guitar
...or for anything else, for that matter.
Ordinarily, the banning of words is bad. But LQQK isn't a word. It's spam. LQQK is only used by those who are purposely trying to use something "eye-catching" in the title of the junk they're selling.
Whenever you see LQQK on Craigslist, eBay or Amazon, report the listing for spam, because it is spam.
Nothing will make me not look at a listing faster than LQQK, because it's the calling card of people that are peddling garbage.
Ban LQQK. Also ban L@@K as well, because that's just as annoying, if not more so.