Try calling other smaller towns in your area to see if they can offer better rates. I once moved from Austin to Boston for $300 on a 14’ new U-Haul truck back in 96. Same truck leaving Boston was $1,200. Originally I priced the smallest truck for $600 which was a beat up toyota pickup and bargained against another local U-Haul to see if they could do better. By the 3rd call, I had a new Ford truck at the next higher size for $300.
I can’t say if you’ll do much better than what you have now since your in San Francisco area, but it’s worth a shot.