What's your biggest trip planning headache?

I don't have a problem with meals or gas, I know how far I can go towing my 5th so about 100 miles before I hit that limit I start watching or check my gps to see what's along the way and how much they charge.   as for food, I pack sandwiches for lunch and if its a multi day trip I stop in a rest area for the night make a little supper and go to bed. 

when I travel with the camper, it doesn't even matter, I can pull into any gas station, and stop in a pullout and make lunch easy enough.  

the problem I have is rv rental companies and tour companies using software to book up all the popular campground the day reservations open before anyone else can get a site on a weekend, or even during the week for the most part.  

After all the years I've been on here I'm almost embarrassed to say my last vacation with my trailer that required a gas or food stop was about 15 years ago. Since then all my towing trips have been under 2 hours each way. But I am thinking about hitting the road this summer so I guess I need to start considering things like routes, campsite availability and such.

I don't really find it all that difficult sans availability which can be overcome by planning early. Seems like creating a solution in search of a problem.

Long drives where food and gas stops are required.  I want both at the same stop and there has to be plenty of room to get around the gas pump and somewhere to park to eat. This is all planned long before the travel date. 

Secondary, I plan routes in advance that take my configuration into account. (Length, height, width).