Just chiming in on an old thread:
When I'm browsing and I look at prebound spirit listings, I can tune into the photograph of the vessel and hear what the spirit has to say... sometimes, it's very faint, and other times I get whole sentences out of them, I can hear their voice quality, pitch, etc. I have no clue how I do this considering I don't have any kind of training and I don't sit around trying to flex my psychic abilities, but it's kind of neat. I do it for hours, sometimes, just to see what each of them has to tell me. It's very entertaining.
I usually say hello and move on from there. If I'm interested in them, I'll ask if they want to come home with me.
The other night I was looking for a mermaid spirit and looked at a bunch of prebound mermaid spirits online and each one was friendly but told me they were waiting for someone else. It bummed me out after looking at approximately 15 listings on ebay... and so I sent in a custom request to Jules (crazy_witchy) for a mermaid.
I also looked at a listing for a green female dragon and she was instantly like "pick me, pick me" when I asked if she liked me. I wasn't even looking for a green dragon to add to my spirit family, but I ended up buying her and a green male dragon from another listing who instantly connected with me and presented as very affectionate and cuddly. I asked if she would mind sharing a vessel with the male dragon, and she said no, so I asked Jules to move the female to the male's vessel and paid for them both.
One time, I glanced at a listing for a somewhat dark Babylonian djinn, which I normally don't do because I don't really care for them and she instantly told me "You don't even like my kind" which made me chuckle
I'd imagine if I didn't have this ability, it would still come through to someone in some way that the item isn't "quite right" for them and they'd move along to the next listing.