Playtex makes a milk storage system that I’ve found to be very useful. You can pump directly into the drop-in liners and store them as is, similar to a milk storage bag. No transferring of milk from one container to the other, no additional cleaning. I’m pretty sure it works with most pump models. I work in a place where I am VERY pressed to return from my break on time, so even that one minute of cleaning is stressful (and therefore affects the quantity of milk I can produce).

Another idea is to save washing by placing pump parts and bottles in the refrigerator with your stored milk. Then you can just pull the parts out for the second session.