Food and service are the biggest part of a party's budget. If you are a good cook and have the time, you are blessed. If you have friends that can help effectively, you are doubly blessed. If not, there is still hope to host a wonderful meal without having to eat a months pay.
Through my experiences as a food service expert (event and catering director for the last ten years), I've come to realize that while most party meals take up only one fifth to one third of the total party hours, the quality of the food and service is half of what the guests remember. They don't remember the expensive rented china or that they used real silverware, nor do they know the amount of work it takes to set up and tear down a fully catered party. But those elements make up the biggest part of a professionally catered meal. You can accomplish for less.
You can purchase wire chafing racks and heat at wholesale clubs or hotel and restaurant supply stores. These are to keep hot food hot. They are lightweight, easy to stack and don't take up much space to store until the next party. Have aluminum roasting pans on hand to use as the steamer element for the chafing racks. Then, through a reputable caterer or restaurant, have the food cooked and delivered in aluminum pans. When you buy only the food, you save nearly a third of the cost.
If it's a large party and you would rather participate than serve, go ahead and hire professional servers. That is money well spent; expect to pay ten to fifteen dollars per hour per each server.
Paper products work just as well as china, and come in an assortment of styles and quality; clean up is unblinkingly easy. Clear plastic silverware, white paper plates and linen-quality paper napkins add a formal touch, or choose bright or pastel colors according to the theme. Linen or heavy napkin-paper tablecloths bring sophistication to each dining table, on the other hand, the white paper or plastic roll is more casual, and most everything can be purchased or rented in a variety of colors.
Folded napkins at each place setting can also illustrate the theme. Large fan-folded linen-quality paper napkins, take on the look of shells for a beach party, or with a little ingenuity, the tails of doves. Add color and they become peacock tails or turkey tails. Or, wrap the silver set in a specially rolled napkin, stand it up on its end and it has the illusion of an unlit candle.
Coil white sparkly pipe cleaners around the Christmas lights to make hanging icicles or use red to depict chili peppers.
Seashells can be bought in bags at many craft stores. Spread them on flat surfaces that would otherwise be unused.