As others have said, do a Google Earth view. My rule of thumb is that if I see a long motor coach in the park, the we "Should Fit" on maneuvering to a site and getting into a site if the site is physically big enough to hold our RV length basis. (Truck not included)
Overtime, I have also learned that if there is a long 5th wheel with 3 AC's on the roof in the google pic, then we'll fit with no issue.
Here is the warning..... It's all on knowing your rig's length, width, turning limitations, and your ability to clearly communicate with your better half in a cool calm collect manner.
There is also an acronym called GOAL... It stand for "Get Out And Look"..... It works wonders when used properly.