My husband just completed his fly/drive trip, and here's a brief report about it. He flew from San Diego to St Louis a couple of weeks ago, to help his sister with the estate auction sale of their mom's household goods. While he was in MO, he had the use of his mom's car until it was sold at the auction. But by then he picked up a U-Haul to bring back goods.
He did very well with the U-Haul rental. The best price was with U-Haul (rather than Penske), and they were easier to get. The local dealerships did not have a 14' ready-to-go for one way, so they rented a 17' for the same price as the 14'. The only thing about that is that the gas mileage was probably worse. Well, it was pretty bad anyway.
He drove from central Missouri to California in 4 days, using I-70 to I-35 to I-40 to I-15. His first stop was just outside of Oklahoma City (around 500 miles), second stop in Albuquerque (520 miles), Kingman (465 miles) and then home (360 miles). He was into his destination within 9 hours the first two days, and just under 9 hours on the third day. On the last day, he made it home in 7 hours.
The U-Hauls get horrid gas mileage, but thankfully they take regular unleaded. He stopped mostly at Flying J and Pilots, because they're usually less expensive, have room for a U-Haul, AND we have the discount card. Every night I sent him a text-message telling him where the FJ, Pilot and Love's were for the next day. That was after he'd stopped for fuel someplace and then found an FJ five miles down the road that was selling fuel for 10c less per gallon! Every time he stopped, he had to spend $50-85 to fill up.
The least expensive fuel he found was $3.17 gallon at the FJ in Albuquerque (before our 2c gal discount with our RV card). The most, as you might expect, was at the Pilot at the Lenwood Exit near Barstow, at $3.69/gal before discount. Most of the time, he was paying right around $3.30/gal.
Before he left, I printed out coupons for hotels that I found online, so that he wouldn't have to stop and look for the booklets. (My husband is a former long-haul trucker. He only stops for fuel and an occasional pit stop.) His least expensive overnight was the Super 8 in Albuquerque, at under $50. The other two were just over $50. I should add, though, that he always asks for a king sized bed, which often costs extra!
As for food, for breakfast the first morning, he stopped at an IHOP and had a full breakfast. That night, he had a later dinner at a Denny's. The next few days, though, breakfast wasn't too enticing because of larger dinners the night before. One night he had food delivered to the motel room and said it was pretty decent! That was Venezia's Pizzeria in Albuquerque, and he had the fettucine Alfredo (one of his favorites). Another night, he walked down to a steak place and had prime rib at a local place ... Dambar at Kingman, though they also go under "Fork in the Road Kingman". He said he enjoyed that, too, and wasn't hungry till Barstow the next day (around 9 am in the morning).
Weather wise, he had NO bad weather except some winds that drove him crazy in NM (head winds, which are NO FUN in a high profile vehicle like a U-Haul). He had a little wind in KS but said that mostly it was tailwind which helped his fuel mileage a little bit. No rain, and definitely no snow which had crossed our minds when planning this trip for him.
Traffic wise ... I-70 was the usual congestion, which is why we've always stopped at a particular IHOP just outside of Kansas City to ride out the rush hour. Then he didn't hit much until AFTER he'd passed through the LA Mess-tropolis, right around Corona. Oh, he had a little bit in OKC and a little bit in ABQ, but nothing major.
He brought us a new atlas - - smaller than we usually use, but informative. We probably won't use it to plan larger trips, but it will be nice to keep in one of the vehicles. It's spiral bound. He hadn't taken ANY maps with him, and didn't want to mess with the fold-out maps that he could have gotten at the AAA in central MO.
We are still unpacking the family items that came back with him. That will be a long process.