Its done. We had friends that traveled out west several times no toad. Big bike riders though thought nothing of pedaling 50 miles a day. Occasionally rent a car.
We did a 12 week swing out west towing a trailer behind our DP. Carried a scooter which let me go for groceries, run errands, etc.
A 150 Vespa will carry two people 60mph and carry an amazing amount of stuff if you have racks.
Enterprise does pick up but that wasted half a day a few times.
They run a route to pick you and anyone else up then drive you back to their office which might be 20 miles away and you rent the car there. Reverse the process to drop off. They don't deliver a car to you.
While we did ok and enjoyed ourselves on the trip we both agreed a toad makes it way more convenient and enjoyable.
My Kharma ran over my Dogma.