CONGRATS!! I love Monterey.
It's not really all that conventional, but if you're open to it, you could ask people to help donate towards your wedding instead of giving gifts.
OR you could just do appetizers instead of full meals. And a paid bar instead of open.
AND Pinterest. Pinterest will be your best friend with TONS of DIY! This company is located in Monterey and may help you with some DIY stuff:
Save On Crafts | Discount Wedding Supplies & Event Decorations You can pick things up there if you're close enough or you can get ground shipping.