Carnival Sweet Sixteen

Hey,
My sister and i are planning to have a cranival themed sweet sixtteen. We are planning to have a dunk tank and big screen with guitar hero on it and alot of other like carnival things ((moon bounce, velcrow wall)). But we are scared for two things. 1)since we just moved to Georgia ((from NY)) we are scared that the friends we have made wont come and that the party would be lame cause we dont know that many ppl. And 2) our parents wont pay for the party unless they invite the ppl they want to ((family and other parents from around the block))

Its really annoying us and we have about 16-20 people comming so far. This is depending on weather or not the ppl from NY we invited can come. This is really getting to us. We need to have an answer soon because our party in going to be in april.