You can not seal or expunged records for employment or housing purposes. And as my colleague stated a conviction may not be expunged from a criminal record.
I published a Guide which may be of limited use to you. The link is: http://www.attorneyqna.com/legal-guides/ugc/what-you-need-to-know-about-criminal-record-expungement-in-virginia . Good luck!
Unfortunately, you cannot have convictions expunged in Virginia unless there was an absolute pardon pursuant to 19.2-392.2. This conviction will show up in public records, and very possibly through background searches.
In VA the only time you can expunge your record is if you were acquitted, or A nolle prosequi is taken or the charge is otherwise dismissed, including dismissal by accord and satisfaction. This does not mean if the case is dismissed based on any contingencies. (Like when a person is told to be good or do community service for X number of hours and the case will be dropped)
In Virginia, expungement for employment or renting purposes is not available after you've been convicted. The law governing expungement in Virginia can be found in the Va. Code § 19.2-392.2 - Expungement of police and court records.