Sometimes they have to take second choice, but they have thus far always found a place. I cannot say

first of all, I'm Johannes from Germany and found this community while I was searching for more information about travelling the American West by RV. I've just registered and hope that you can help me.
We booked an RV from San Francisco to Las Vegas in July (End) and August. Our route contains holiday car rental paris the following main stops(so far): San Francisco, holiday car rental paris Monterey, Los Angeles, Calico, Bullhead City, Grand Canyon, Lake Powell, Monument Valley, Bryce NP, Zion NP, Las Vegas.
- We don't want to book all available RV campgrounds holiday car rental paris in advance holiday car rental paris because we're not sure yet where we want to stay for how long. We found many alternatives, for example: parking at Walmart or simply at the roadside. Is this possible? Can we travel this route this way, i.e. without any reserved campground?
And you will how to figure out transportation from RV campgrounds into the cities you want to see. LA is a special issue - since it really isn't doable by public transit and driving around/parking an RV might be challenging
Many towns in the west/southwest do have dumping facilities but I would make sure to know where they are and how much room is in holding tanks etc. Not sure about how often you need to charge electricity etc]
Many Walmarts holiday car rental paris have stopped allowing RVs to park there and no you cannot just park your RV along the side of the road anywhere (although I have read this is possible in National Forest lands) or you might get asked to move on, or issued a fine.
OK - have you prepaid for the motor home? If so you are sort of stuck. But if you have only booked/paid holiday car rental paris a deposit I'd VERY seriously consider canceling. The places you want to travel are not nice in an RV in the summer. You will need to run the air conditioning all night to hope to get any sleep. You would be able to cover more territory easier/cheaper/faster if you rent a car and stay in motels. In fact I'd even consider canceling if you've paid a non-refundable deposit - unless it is a huge amount holiday car rental paris of $$/
But if you have pre-paid in full, and must return the vehicle in Las Vegas then yes, you are stuck - I'd maybe consider changing plans and heading north-ish after SF and the coast (Lake Tahoe, the Sierra) and end up in Las Vegas to drop the RV. Or even head north of SF along the coast and then hit Lassen before Tahoe etc.
I live here and wouldn't do it and I drive these roads daily. Not in a big honkering RV. Narrow roads - 1 lane in each direction that were not built for wide loads; steep drop-off with no shoulders; steep grades which are as tricky going up as down and the every present person who is nervous and rides their brakes only to have them burn; curvy roads where you can not always see oncoming traffic and all those other people driving RV's for the first time - in front of you, behind you and coming at you. Summer is my least favorite time to live in the mountains.
What is wrong IMO is spending a huge amount of money for a one-way RV rental, over seriously holiday car rental paris twisty/narrow roads (Big Sur won't be hot but not a fun road in a motorhome) , in the heat of the southwest in August. Can't think of much 'right' w/ that plan.
I've full time RV'd for 4 years and thereafter and continuing this year to Sturgis Motorcycle holiday car rental paris Ralley and later to Baja California (Mexico). Higly recommend RV travel. BUT - look for a Class C RV about 27 feet that is manageable on any paved park roads.
holiday car rental paris As others have pointed out, you may find trying to visit some of the paces on your list difficult in the RV. Another consideration is that even if you can access these places with the RV it means you have to "break camp" every day - stowing away anything you've taken out. We tow a Jeep behind our motorhome for these very reasons. Also, if you aren't accustomed to driving one, that could also be a factor.
As for finding a place a stay without holiday car rental paris reservations - much will depend on the day of the week and if there are any special events occurring at the same time you'll be in a given area. Some Wal-Marts allow overnight parking - others do not. If it's hot, you'll have to run your generator if you're "boondocking" - which is what most people call staying in an RV in a location which doesn't have electrical and/or water hook-ups. This doesn't just refer to Wal-Marts and such but also to some National Forests and Bureau holiday car rental paris of Land Management holiday car rental paris areas.
Sometimes they have to take second choice, but they have thus far always found a place. I cannot say if this will be your experience as you are traveling at a different time of year - they were in Arizona late April and Utah, early May. In the Grand Canyon they did what they call 'dry camping' (no electrical hookups) and used flashlights, etc. instead.
To the best of my knowledge, they didn't do any 'free-camping' i.e. parking at the side of the road. I don't know if this was personal preference or because it was the local law, but they have always used RV parks. This may change once they get to the Yukon.
Before leaving home, they did a bit of practice driving. They are used to driving a truck, but even they found their RV to be wider than what they were used to. Also the turning radius was much larger - something to be aware of in gas stations. If you can, get in some practice with an RV of similar size before you leave Germany.