As a veteran mover, I recommend you
don't use U-Haul. I've had the worst experience with them, as well as many,
many people I know. They're unreliable, their trucks aren't well-maintained and they break down, their customer "service" people are rude, and they're just plain awful. Perhaps they've improved in recent years, but better safe than sorry! You don't want to be one of the many stalled U-Haul trucks I always see alongside any major freeway.
U-Haul does, however, sell a fantastic selection of moving and packing supplies (boxes, bubble wrap, blankets, etc) and they're fairly cheap. Do invest in quality packing supplies, you won't regret it! And they're usually really easy to re-sell when you're done with them, if they're gently used.
I always had good experiences when I rented Ryder or Budget Trucks. Very well-maintained trucks and no service problems.
I always swear I'm gonna hire movers/packers next time I move, but then I run out of money and end up cursing and threatening that for sure,
next time will be different...