Road dogs hightailing it along I-90 can save some scratch by stopping at Shangri-La Motel (2922 W. Government Way, 509/747-2066, $45), a bare-bones but clean and safe crash pad perfect for a night or two’s rest.
For slightly more comfortable budget digs, try Comfort Inn North (7111 N. Division, 509/467-7111 $75 d), one of the better chain motels in town. This place is immaculate, it’s got a pool, and you’ll be greeted with fresh cookies upon check-in.
Or, for a little touch of home, stay at 
Marianna Stoltz House (427 E. Indiana, 509/483-4316 or 800/978-6587, www.mariannastoltzhouse.com [1], $89–109 s). Set in a classic American foursquare home built in 1908, this affordable bed-and-breakfast stands on a tree-lined street near Gonzaga University [2]. A wide veranda, spacious parlor, and antique furnishings add to the allure. The four antique-furnished guest rooms have private baths.
Links:
[1] http://www.mariannastoltzhouse.com
[2] http://www.moon.com/destinations/washington/spokane/sights/universities-and-colleges