potluck wedding

Hey everyone
I plan on having a potluck wedding reception at our home this year and I need help answering a VERY important question: when should the food family members are preparing arrive at our house? Like, before or after ceremony (1PM)? Also, who do I entrust with picking up foods from catering companies and bringing them to my house? 
Note: I just need feedback on how to make this work. I don't need to hear how tacky of an idea you may or may not think it is.