This is a great opportunity for you to get some performing experience!
I would recommend that you tell the host ahead of time that you do some magic and ask him/her whether
they would like you to walk around and entertain the guests with a few tricks at the party. They are almost certain to say yes, but this will show some respect and make it more likely that the host will pave the way for you by mentioning to people either before, and/or at, the party, that you are going to do some magic. Be sure to mention to the host that you do not expect any compensation for this.
Also, unless you are planning to do a stand-up show, I would make it clear to the host that you do "strolling magic," in other words, just walking around to the various guests (whether they are sitting at a table, standing around, or whatever), and doing a trick or two then moving on to other guests. I suggest that you resist the temptation to do more than a trick or two for each person or small group that you approach. It's good Show Biz to "leave them wanting more!"
Finally, you mentioned the nest of wallets. That is one that plays big that you could do as a finale or "mini-show" for everyone after you have done your walk-around. You could also do the Invisible Deck for the entire group at the end as part of a mini-show, if you do that one. Just tell the host that you would like do something for the entire group and he/she can inform everyone and gather them together for it.