Bonding a trio

I've decided to give this a go soon. I'm hoping Honey my single female will help the other two girls relax around people a bit more. It won't be until Honey has had her bad eye fixed but want to prepare now. I've been looking at their personality and I think it will work.

First off as I don't have neutral space other than a very small bathroom I was thinking of buying a second hand pen spraying it with vinegar and putting it I'm the lounge, which I was also going to clean with a bit if vinegar. Would this be OK?

Also who do I put in first? The pair or single?

What signs mean it definitely won't work?

I think a second-hand pen will be fine and if it is boy/girl you are bonding we always put the boy in first as he is supposedly the dominant one. I would be inclined to put the single girl in first although I've never been brave enough to bond 3 girls!

I'm probably mad lol they all seem interested in eachother. They sniffed eachother through bars. But I know that's no indication of how things will go. If it doesn't work that's OK too. We'll see