As you have been waiting for quite some time without any other experst assisting, I will return to try to assist.
As for your question about whether the owner can request the trailer be moved after sale, the answer will largely depend on any agreement you signed when you first moved there. If you brought your own trailer and are merely renting the space from the owner, then such a rental agreement will likely only bind you and the owner. As such, once the trailer is sold, the owner would have no obligation to continue renting that space to the new buyer and thus could demand they move if the owner doesn't wish to rent to them.
As for your question about the owner wanting nothing to do with the realtor or prospective buyer, this is a concern since you mentioned you need his approval to sell. In most of these types of cases, there is a contractual term, whether express or implied, that the owner mustn't unreasonable withhold consent to sell. In other words, the owner is not to flat out say NO for no reason when you request he approve the sale. This arguably also applies in the sense that the owner cannot refuse to meet anyone thereby making it impossible for you to sell. As such, you could have the owner sign a document stating that he consents to the sale. If he signs this, then you could sell it without the need to have the realtor or buyer meet with him personally since his approval is a blanket statement in writing. If the owner refuses to sign such a form, and refuses to meet with the realtor and prospective buyers, then it seems as though he'd be breaching the aforementioned provision that he is not to unreasonably withhold consent. Accordingly, you could try suing him for breach of contract- or alternatively, the threat of such alone may be enough to 'scare' him into cooperating with you in this sale. In any event, it seems you have some legal recourse in this regard.
Hopefully that is of assistance.
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