Depends on the type of property, the controlling law, and your status. None of which are clear in your post. There will be lots of 'ifs' in what follows, but here goes: Generally,
1.IF you are the owner/landlord of the property, and the IF property falls under the Virginia Residential Landlord Tenant Act (VRLTA) by contract provision or operation of law you would have to take a few steps before doing anything. You could claim it as abandoned so long as you:
(i) [gave] a termination notice to the tenant in accordance with this the VRLTA (Code of Virginia 55-248- 38.1) chapter, which includes a statement that any items of personal property left in the premises would be disposed of within the twenty-four hour period after termination, (ii) given written notice to the tenant in accordance with § 55-248.33, which includes a statement that any items of personal property left in the premises would be disposed of within the twenty-four hour period after expiration of the seven-day notice period, or (iii) given a separate written notice to the tenant, which includes a statement that any items of personal property left in the premises would be disposed of within twenty-four hours after expiration of a ten-day period from the date such notice was given to the tenant. (See PROPERTY AND CONVEYANCES. Chapter 13.2 - Virginia Residential Landlord and Tenant Act (55-248.2 thru 55-248.40) 55-248.38:1 - Disposal of property abandoned by tenants)
2. IF you were a mere tenant just like your roommate was (i.e. you have a landlord), the property never becomes your unless you had some agreement with your prior roommate. It would become the Landlord property
3. IF the roommate left the items with the expectation that you could use/hold on to them for roommate, then you can consider them yours only when you give proper written notice to the roommate, tell roommate you no longer wish to 'watch' his items and demand he pick them up. You should document what the items are (pictures are great), list them on a document and send same to roommate. If roommate fails to claim after a reasonable period you could consider them abandoned. It would be possible that the LL could step in and claim the items as abandoned, but very unlikely, and you could probably consider them yours.
4. IF you rental agreement is NOT covered by the VRLTA, and you are a roommate, it would likely go to the LL.
5. IF your rental agreement is NOT covered by the VRLTA and you are the owner/landlord, you would likely have to provide the same kind of written notice as above, before claiming the items as yours.
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