For the the sake of the OPs' original questions.
Yes, I wouldn't start from Florida either, but there you go.

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Dave

As a reference point ...
I have probably spent some 2 to 3 months in the UK. Say 7 months in western Europe.

None of my trips have been long enough!

Do go, but allow that the 'plan' you make will not be what you do. You will miss things ... sticking to the 'plan' or not. Not sticking to the 'plan' will mean you see different things. And maybe less of the country .. but in more detail. No matter what you do .. there will always be more to see.

I did something similar but we took 10 weeks and took the Northern route to include Route 66. Here are my thoughts

3 weeks, that's a long way to drive

Have you considered rental car drop off fees as you are doing a 1 way rental

If you use hotels then join the frequent stay programme, we did Choice Hotels which includes lots of the not quite so budget hotels. Every stay gets points and we used the points to get a room for free in expensive cities

Choose a hotel that gives free breakfast to save on costs

Use supermarket for lunch

The park pass is $80 but if you are going to visit a lot of parks it will save you lost of money

September it will be quite warm

3 1/2 weeks. That's going to be tough.

If Disney World is non negotiable then I would stay on the east/south east coast and explore. However, it's going to be hot and humid.

I know you want to do as much as possible, but you might consider significantly downsizing your trip. For 3 1/2 weeks I would fly into California. You could see Yosemite and Death Valley (from your well air conditioned car) National Parks (amongst others along the Sierra Nevada). There is amazing hiking on the west and east sides of the mountains. Do not attempt hiking in Death Valley, it will be 100+ in September.

Drive from the west side of Yosemite to the east until you get to Highway 395. You'll drive over and down Tioga Pass (Tuolomne Meadow is a must stop and hike). At the bottom is Lee Vining (cute little town, try the private campground on the north west side of town) and Mono Lake (visitors center in town, the lake is a very interesting part of California history and ecology). South of Lee Vining is Mammoth Lakes (ski town, try the campgrounds above town, Lake Mary is nice). Very cool geology and again great hiking. Visitors center on the way into town. North of Lee Vining is Bridgeport, another neat little eastern Sierra town. The canyons above are fabulous. Try the hike from Virginia Lakes to the top of the pass (passing Blue and Frog Lakes).

There are other amazing roads in the Sierra, pm me if interested.

Read up on Highway 1, the drive from Morro Bay to Monterey (or continue to San Francisco) is spectacular. Make sure to stop in Big Sur and tour Hearst's Castle. The Monterey Bay Aquarium is a must. Also lots of great hiking along the coast.

San Luis Obispo is just inland of Morro Bay, fun college town. Plan to be there for Thursday night Farmers Market.

We don't have Disney World but we do have Disneyland.

San Diego is a very fun city. Make sure you hit the Gas Lamp District. Rent bicycles and ride Silver Strand.

My favorite beach town in SoCal is Laguna Beach.

Las Vegas isn't too far from Southern California.

You could also loop out to the Utah National Parks and Grand Canyon.

We do have hostels, I'm not sure if you'll need to make reservations or not. The cheapest motel chains are Motel 6 and Super 8. Best Western prices really vary with location (like the other motels/hotel chains) but are pretty consistently good. I would pick up a Frommers Guide to help with lodging choices, I've had good luck with the California one over the years (and I live here!). You'll have to really be careful with your lodging budget.

Bed and breakfasts here tend to the expensive, we have very few of the inexpensive B and Bs you have in the UK (which were amongst my favorite places to stay when I was there this summer).

If you use grocery stores you should be ok on $50/day for food. But that's eating out very little. I would do some really, really cheap food days and save up, there are fantastic restaurants wherever you end up.

Happy planning!

Las Vegas is a great place for travelling. There are some place listed here http://casinority.com/most-expensive...uildings-ever/, which are really worth visiting.

If food is important....I would not miss Louisiana cuisine.

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journeyman

Hi Skyroads,

My opinion is that 3 1/2 weeks is too tight for what you want to do without spending too much time driving.
I am a bit biased since I live in Southern California but I really, really like Little Bikes suggestion, hitting San Diego, the coastal route to San Francisco, (skip LA) Yosemite, the Eastern Sierra Nevada Mountains, Las Vegas, Grand Canyon, etc.
You won't have a rental car one way drop off fee if you do a loop.
At any rate I would focus on a smaller part of the US if you only have 3 1/2 weeks wherever that may be as long as it is seasonally appropriate.
Have a great trip!