I have difficulty in renting an apartment in Virginia because of adverse credit report. How do I get over this? Can I get a friend to co-sign for me?

If time and funds permit, you can try to clean up your credit to an acceptable level. To get a friend to co-sign the lease will be hard. It will have to be a VERY GOOD and perhaps stupid friend to jeopardize their credit, and run the risk of making your lease payments, should you default. You might offer to put up additional security deposit, to the limit allowed by local law.