Ok. Get rid of any duplicates. Everything. Set aside 3 hrs a day. Set a timer. Donate the items.
Next, look at the boxes you’ve already packed. Without peeking, do you remember what’s in them? If not, donate.
When we die, we cannot take items with us. Everything that enters your house must be either useful, beautiful, or displace something else. Use the one in one out rule in the future.
Purge as much as you can. Advertise a huge free garage sale on CL. Remember to set aside time each day to accomplish this.
Rent a PODS and out your boxes in there. Hand carry the breakables, as well as valuable files, etc. Movers are $$ and things get lost.
The bottom line is purge what you can, now. I’m so happy you’re leaving DC. I was too.
(Ps- pay to have it staged. That way you can move everything out of it to your new place. It costs money but I guarantee it helps houses sell faster and for more money)