My tenant has broken the lease and moved out early. I am in the process of getting a new tenant. She still owes me rent for January & February because the lease doesn't expire until July. Even though I already have possession of the property, do I still send the pay/quit notice to include January & February rent/late charges? I don't want to file an unlawful detainer until the home is rented and I know exactly what is owed. I only want to go to court once, if possible.

I live in Virginia.

Did the tenant turn over the keys? Or did she just sneak out? This is key, because unless the tenant formally gave up the unit, then you may not have a right to regain possession. In that case you probably would need to go through the Pay or Quit. But if they gave you notice and handed over the keys, then you have possession. You can then rent the property and after the new tenant has moved in, sue the previous tenant for rent up to the move in.

She did turn over the keys, so I already have posssession. So, should I not send the pay/quit and just wait to a file an unlawful detainer?

Yes, she formally turned over the property to you, so she already "quit". No need to give her a pay or quit notice.

Yes, you need to continue to bill them for all of the rent due, adding late changes. Since this is a on going debt till it is rented, then after you rent it, and all of the charges including late fees are due and not paid. Then you sue them in court for the damages if they don't pay