I live in Virginia. How can I get rid of a friend I let stay with me on a short term basis? He's been here now for approximate 30 days. I'm the only one on the lease with the homeowner. He'says I have to give him 30 days notice, is this true?

Some friend, huh. Here is the process that must be followed, note if the "friend" is endangering you you may be able to do an immediate eviction. Virginia Eviction