having done a low cost wedding,i must compliment you for setting a budget... which is ok... but coast is expensive ... unless all your rela's come from there.... you need to budgeted for accomodation,transport,catering (sic),flowers,outfits,cake,gifts,venue,security,etc... but the surpirse part... i am not convinced it will work.
I would have said something smarter..but the moment passed