The same questions keep being asked over and over, so let me just consolidate everything into one thread.
Etiquette is not a subjective thing, and it is not a budget thing. Etiquette is a set of very basic rules which, like it or not, dictate any social gathering which you will be hosting. Yes, a wedding is a celebration, but from the second you invite ONE other person aside from you and your FI, you have to follow proper hosting etiquette. You will be the host.
FAQ in comments: