If you're looking for a long term stay RV Park, Island Cove is one of the few you'll find for under $500 a month in the Portland area that have monthly rates available (Multnomah County actually has a law not allowing extended stays at RV Parks). The closer together front side-sites are 30 amp and $350 a month, the back, more spaced out sites with the concrete pads and 50 amp service, "Premium" as the previous reviewer called them, are $400 a month. The park does have Wi-Fi, however, the speed can be hit and miss as its satellite based (No wired High Speed is available past the County Line). We camped here in a Truck Camper.
We did not stay here. We didn't have reservations, called and spoke to on-site manager who was very helpful and had a couple of open sites. We pulled in and were somewhat put off. Appears mostly long term residents, some sites were junky and on lawn area. The premium sites were cleaner with newer units on concrete pads but none available when we needed to stay. We were not willing to stay in the lower cost area, it is not our style of camping. Cash only at this park if you intend to stay: we were quoted $30/night. We camped here in a Travel Trailer.
We didn't actually stay here, but drove up to see if it is a possibility next time we come to Sauvie Island. Its a nice clean campground. The RV sites were close together, but adequate. It also has tents and yurts to rent. Its across from the Yacht Club on a small inlet and about 2 miles from the public beach. Spaces were not as far apart as at Reeder's, but less permanent residents. We camped here in a Travel Trailer.