Buttercream frosting will hold up fine in warm weather - definitely do NOT use whipped cream frosting when it's warm - it will melt - take it from a decorator! I would decorate the cake the night before (where I work I decorate the Saturday wedding cakes late on Friday night),
We spent more than we wanted to on the hall, but because is was a new venue it was far less expensive and it is now, 11 year later. My mom, girlfriend and I did all of our own decorations. My aunt is a cake decorator so she did my cake. Now I'm a cake decorator :) Here's a tip about ordering cupcakes as someone else suggested - we charge more for fancier cupcakes, so if you can, just get them iced and order jimmies on-line that go with your theme. You may want to consider ordering full-sheet cakes that are pre-scored with a small sweet-pea on each piece. This is easier to cut and serve, and way less expensive. You can have the colors done to match your theme. You may want to consider NOT telling them it's for a wedding - I've seen the same cakes up-charged because it's for a wedding and for that reason only.
For a friend's upcoming wedding I'm doing her cake from my home - but I'm doing small individual cakes. I will start a couple months early and freeze them ahead and decorate the day before. If done properly no one will know the difference. I will probably use large muffin pans or egg-shaped pans for that. Then she can have a large variety of flavors and serving them is a breeze. She's also serving nice hors d'ouvres instead of a meal so the price is significantly less - about 1/3 the cost. ... View related article.