On the down slope of moving right now, you just don't realize how much stuff you have till you got to move it...
I've helped quite a few people move.
The worst thing to move is the hide-a-bed. Those abominations are stupidly heavy, awkward and very often can't be taken apart. Plus they often aren't that comfortable to sit on, let alone actually sleep on.
Older model washing machines are a close second since they have heavy metal drums inside and just weigh a ton. Plus they're usually in the basement so up a flight of steps with them. To make matters worse many older homes don't have very high ceilings or wide enough passageways so it's a very tight fit.
Surprisingly the easiest thing to move is often the empty deep freeze. They're deceptively large but they're usually pretty light compared to other things.
If I had any advice for people moving it'd be to have things packed up the day before. Seriously it takes so much longer to get done if the packing side isn't already done. Don't wait until moving day to empty the cabinets of dishes. Get any glass or trinkets wrapped up early on, clearly label them and get them out of the way.
When packing books only use fairly small boxes because books get heavy in a hurry and using large ones means it'll take 2 people to carry them and the bottom has a higher chance of breaking open.
If you have pets... either lock them in a room or have someone else look after them. I know it may sound harsh but they just get in the way. It's a massive pain to have to constantly be opening/closing doors to keep a cat or dog in when trying to carry large or heavy items out or in. Last thing you want is a dog/cat to try zipping by just as something heavy slips from fingers. It'd be bad enough to have a heavy desk/cabinet/tv stand/whatever drop and maybe break. But to have a pet get injured in the process too? Be even worse.