Well, I had the best deal. I stayed with my son and family when he was at the Naval War College.
As for tours, we bought tickets and then took our time going to each of the mansions. They are all close together. I believe it is about $60-70 a person, but it is worth it. Some wonderful houses. At the mansions, most, if not all, have the "Auto-tour." You get a headset and recorder and you can go to any section of the mansion on the tour and have the recorder tell you about it. Parking at the mansions is easy, but weekends are definately more crowded so try to make it a weekday tour.
As for campgrounds, there is only one that I would stay at, well maybe two. The second choice one for me would be " Second Beach Family Campground."
My first choice would be Fisherman's Memorial State Park
and is only 22 miles from down town Newport.
There is a toll bridge going into Newport. It is $1 each way. If on the first go through you stop and ask for a roll of tokens, you will pass through free that time. If you are in a 1 ton dually they will not sell you tokens. I just happened to have my Texas registration with me and it proved that I was under 8000 pounds and they sold me the tokens. A comment was made that they never had a dually weighing less than 8000 pounds. Sorry!
You do not want to take a MH or a trailer through the streets of newport. They ARE tight. I drove my then F350 CC LB King Ranch and there were turns I would not even attempt.
Newport is a wonderful city, and a large tourist attraction. Make sure you take a cooler with you, go to the wharf, and buy some lobster at $8 eash. Take them back and throw them on a hot grill for about 15-20 minutes. MMMMGood!
If you look at this via satellite you will see the spacious sites at this Fisherman's Memorial State Park.
The Second Beach does not allow pets.
Edited: There may be restrictions on electricity at the state park during peak times of heat.