Your last response is puzzling. Previously you said that he claimed X violated the town/county ordinance. Now you are saying that he is claiming you violated the homeowners association?
Let me put it this way, if someone is saying something factually untrue about you on line, then you have a claim against them and potentially against the online forum for defamation.
In Arizona, the elements of a defamation claim are:
1. a false statement concerning the plaintiff;
2. the statement was defamatory;
3. the statement was published to a third party;
4. the requisite fault on the part of the defendant; and
5. the plaintiff was damaged as a result of the statement.
Morris v. Warner, 160 Ariz. 55, 62 (Ariz. Ct. App. 1988).
To be “defamatory,” a statement must be false and bring the defamed person into disrepute, contempt, or ridicule, or impeach her honesty, integrity, virtue, or reputation. Godbehere v. Phoenix Newspapers, Inc., 162 Ariz. 335, 341 (Ariz. 1989).
In your case, if Mr. X is making a statement on Paypal that you did not provide service that you actually did provide, then Mr. X is technically defaming you. You can sue him and Paypal for publishing the defamatory statement. You have to be able to demonstrate that his statements are causing you a loss in renters
This is the legal mechanism that can force paypal to take down the comment. The first step, of course, is a legal demand letter. You need to send the letter to both paypal and to Mr. X telling them that they need to immediately take down the post or you will sue for defamation. If they do not take it down, then you file suit.
The other way of doing things is to post a defensive statement on paypal and then have other renters post positive statements about you on paypal...that way Mr. X's negative comment would be overshadowed by the positive comments.
Please let me know if you need further clarification.
Zachary D. Norris