Need Help In Bringing This Idea to Completion

Hi all,
I have a gift basket business.
I had a great idea for Valentine's Day. I am going to try to get my existing apartment customers to let me hold a Valentine's event in their clubhouses. I am going to ask my existing customers first. I want to offer their residents a benefit of the convenience of shopping for a Valentine's gift without even having to leave their apartment community.I would set up a table with sample baskets and have plenty of business cards to hand out. I would bring order forms so people can place orders. I will also have food samples to give out and I was going to bring sodas for people that inquire at my table. I was also going to give the prop mgr a valentines basket to raffle off to their residents for valentines day. or if they want to use it for giving to someone that gave then a referral or whatever.
My question to you all is this: I was thinking of getting 2 other local small businesses to see if they want to come also and set up tables to promote their products( one is a candy bar wrapper lady, the other is a pet sitting person) How should I go about asking these other businesses if they want to do this with me ? I have spoken to the candy lady on the phone once before the holidays. The pet person I only talked to by email. I think it would be beneficial for me to say " it will be Aunt Anna's Baskets as well as ___, and _____" Then they could really promote it to their residents and more residents might come if more than one vendor would be there, right?
Help me brainstorm please. I want to start promoting this soon if I can.
Thank you
Anna