I was looking when I went up for a few alpine courses, Sandy was the cheapest with an hour drive. What I ended up doing the first night was borrow my dads truck and slept in the back. Miserable night, 40mph wind and snow. Decided to just drive from my folks place which was about 1.5 hours. Other option is staying in Hood River, still about an hour drive.
I've always spent the night in the Timberline Lodge parking lot in the back of my truck. Probably the closest motel would be the Best Western in Government Camp (can't verify personally, just did a Google search).