What a amaging suggestion!! Thank you for your professional advice and generious sharing. I hope I can see those beautiful scenes directly soon by myself.
You are welcome. By the way, you only need to book one room for your family, double rooms in motels and hotels in the US normally have 2 queen size beds.
Staying and eating in hotels in Nevada will be cheap as long as you don't gamble. You can check out these two sites of Las Vegas:
http://www.vegas.com/
http://www.lasvegas-entertainment-guide.com/index.html
The following are photos of the three hotels I stayed during my three trips to Las Vegas, plus a photo of New york New york Hotel. You should be able to book Circus Circus, Excalibur and Luxor for under US$40 for weekdays. Some of the newest hotels, such as Paris, were not built when i visited, but they will be more expensive.
By the way, the following photo is Laughlin in Southern Nevada. it is close to the freeway between LA and flagstaff, gateway to the grand Canyon South Rim. I remember the hotel I stayed there charged under 20 US dollars for the night, and the next day we had a buffet brunch that came with a bottle of champagne for under 5 dollars per person . Great deal.
if you are going to visit 5 or more national parks, buy an annual pass at the gate of the first one you visit. It costs US$80 and is good for a car and all its passengers to enter any national parks or national monuments for one year.
Individual parks cost between 10 to 25 dollars for a 1-week permit (a vehicle plus all the passengers in it). popular ones such as Grand Canyon, Bryce Canyon and Zion cost 25 dollars for the permit.