On RT82 Richland Hill has 7% grades with tight turns (expect 30- 35 mph road way) and Minam Hill Summit has a 5% grade for 2 miles and has an Eastbound descent of 4-6 % for 4 miles. A good source is the Mountain Directory.
We recently stayed at Granite Lake Premier RV Resort. Get a Lake/River view (Snake River) site and you'll be very happy with your stay. Close to (everything) and yes, a Snake River jet boat ride (Hell's Canyon) is a must. We highly recommend this park/resort. Happy travels