Obviously the total cost will depend on the destination chosen, number of guests and the style of the wedding etc.
Because of the nature of a destination wedding, it's not considered a social faux pas to restrict the guest list to close friends and family - meaning that the total number of guests is usually substantially lower.
If you choose a destination such as the Spanish Costa Blanca, with it's low travel costs and good value for money, then the total cost of your wedding will undoubtedly be lower than for a traditional wedding.
Who pays what ?
As with a traditional wedding, all the costs for the wedding day are paid by the bride and groom, or their family.
The difference is in the travel and hotel costs, which are usually paid by each individual guest.
Guests are then free to choose the length of their stay, and if they want to combine the wedding with a long weekend or holiday.
In some cases the bride and groom (or family) pay for travel and accommodation for all the guests.
According to destination wedding etiquette, it's perfectly acceptable to ask a guest to pay for his own travel and hotel expenses. Of course in that case, the guests must be allowed to choose their accommodation and the length of their stay - although though for practical reasons most guests usually stay in or around one place.
Destination wedding etiquette also requires that the bride and groom, or their wedding planner supply each guest with information about the destination, such as sightseeing tips.