Vintage on line

We have decided to finish our basement. We plan on staying in this house until Emma leaves the nest and the girls and their friends need space to spread out. This has been a long & difficult decision for us. Almost as difficult as deciding whether or not to have another child. The way I figure it, having a basement will cost much less than having another child. Plus, basements don't talk back. Decision made. Easy peasy.

I want a beach house cottage feel for the basement. That way when we eventually buy a home on the water (in approximately, umm never) I will be all ready to decorate it. It's scary how my mind works, isn't it?

This space is about 1200 square feet which sounds big enough until I start listing all of the things it has to hold: media area, game area, play area, workout area, mini bar, storage, guest quarters and a full bath. I keep reminding myself that my first house was smaller than this and managed to contain 3 bedrooms, 2 bathrooms, a family room and an eat in kitchen, so I know it can be done.

I'm nervous because this will be my first home renovation project. I'd love any general advice on renovating & also specific advice about basements that any of you could give me. Tips on keeping costs down would be helpful too!