The key is if you are not a "paying member" to only choose a short duration for your ad, say 1 to 2 weeks. The ad just expires then you can just make a new one if it does not sell. You can also just mark the ad as "sold" this will also cost you nothing and will remove the ad.
You can not change anything in the main body of the ad once you submit it, whether you are a paying member or not. You can add additional paragraphs to the ad but nothing to the original main body. The reason behind this is to keep people from "altering" ads after something gets sold to keep from saying "that was not what was was originally described in the ad" in other words it protects the buyer.
Just like nything else you sign up for its all in the rules, just most people do not take the time to read the fine print and then just want to complain about it after they discover problem
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Chris
As close to "Normal" as I can get...
