None of the Flagstaff area RV parks are all that great.
Instead we stay 20-30 miles west in Williams, AZ. Circle Pines KOA is a nice, clean forested, dirt road campground. Many spots are large, big rig.
Grand Canyon Railroad RV resort. This is in Williams next to the Grand Canyon Railroad and hotel. RV guests can use the hotels indoor pool. Very nice paved RV resort. General store and pet kennel on site. This is our favorite. Williams is a great route 66 town right off I-40.
Below are Flagstaff area RV parks we've been too.
Woody Mountain. This would be my pick if you must stay in Flagstaff area. Forested, dirt road campground. Clean, very nice employees. Big rigs can be a problem as some spots are narrow and numerous trees to maneuver around.
KOA east Flagstaff is very cramped tight spots.
Munds Park is clean but most spots are out in open treeless area. Much of the park is now permanent rentals. If you can get a spot in the forested section you'll be good.
J&H RV Park. Clean, open gravel lot. Mostly 55+ but they do allow kids. Most of the residents have lights out and inside RV's by 9pm.
Fort Tuthill Park. Forested state park. Most sites have water only, no electric. A few spots have sewer.
2014 Winnebago 26FWRKS 5th Wheel
2007.5 Dodge 2500 6.7L Diesel
2004 Dodge Durango Hemi 3.55 (Used to tow TT)