I have a trunk bag that has a 2nd zipper like a suitcase so it can expand upward for larger cargo items. Also the sides open and drop down into large pannier bags for bigger items.

My grocery setup:

I use a couple of bikezacs and have a frame connected front rack

I bought an old kids trailer for 20€. Cut of most of the structure and transformed it into a cargo carrier. It can also be converted into a table for use at parties and protests, haha.
I can also recommend these click-systems that come with certain racks. Got some stackable Euroboxes to mount on those.

Do not carry grocery bags from your handlebars. I did that when I was a teenager and now I have bridgework where my upper front teeth once were.

Misread the byline as "Max Mounter" and thought that's rather on the nose

This website is a fantastic resource I'll absolutely be sending people ask questions like these, no more lengthy explanations. Thank you for sharing!

I have moved twice by a bike & trailer, although both times the distance was just a couple blocks. The first time I moved all my stuff (except bed) to another flat and the second time we moved our bike shop to another location, for some heavier items we used a car. Also I've carried furniture on a bike, one time a pretty hefty tv table on the rack (with another person walking by and balancing it). I find it amusing that it's possible to carry a whole table on a bike but not in a (regular) car! :D

I've moved full other bikes, big plants and all sorts of stuff using bikes.

Eg. long cargo

Really stoked about this trailer for going between bike and bus with cargo

Useful useful! I admit I early on bought saddlebags and have a backpack I'll take when I go grocery shopping on my bike, when I had a grocery store at least.