A good rule of thumb is that being inside a building with other people is about the most dangerous thing you can do right now.

Wear a mask, wash your hands, keep your distance, but for what it's worth my main priority based on everything I've read is doing what I can to avoid breathing the same air as strangers for any appreciable length of time

"Are you open for pickup?"
"Yep, just come inside and pick up the item"
"Ah, no, sorry, I don't enter buildings"
"Oh, okay, we will bring it to the door"

^ a phone conversation I have had several times in the last few weeks

Not everyone has a choice about being inside buildings with other people. But if you CAN choose, and you choose to do it anyway, you might be the one bringing the virus in. Less contact is better for everyone.