Look at it from Iboat's perspective, as a huge retail parts outlet and a used boats for sale listing service (and IDK, they may offer more used boat's services then just listings) it might get tricky if 2 users agree to a transaction via the forum, in a litigious society, where 1 party or the other in that transaction could attempt to hold Iboats liable if a transaction doesn't suit them just because it was done in the public domain and Iboat's
'should' (could(?)) have been aware that 1 party was acting in bad faith.
I'd rather avoid trying to re-sell my excess xyz parts & pieces all together rather then wading thru the entire iboat's catalog to ensure it's not something they offer to sell currently, or an item that is very similar to an item they sell. If I worked for Iboats, I certainly wouldn't want to be tasked w/ keeping an eye out for listings for items we sell in every corner of the forum.
Not on a forum of this size, w/ as many subforums as it has.
Best to just make a blanket, all in compassing rule:
8. You may not solicit any personal transaction (buy, sell, rent, trade free, donate, etc.) in the forum
If it's kept to PM's, then it is in theory, by it's very name,
private and just between the 2 users in the discussion.
And at least for me, it's what makes it entirely understandable (I'd expect nothing less from any other retailer hosting a public forum) that iboats redacts postings, listings or names of their competitors in the market place, online or B&M stores, including epoxy/poly resin suppliers since they now carry a fuller line of those products too.