I'm going to promote from a reply a bit of analysis of what my options are on hotel rooms, along with a selection of room prices that I hope explains why I'm hunting around the low end.
I am not staying in San Francisco, which is 30 miles north of me. I work in Mountain View, on the Peninsula. Anything there, or San Jose, or Southern Alameda county (Hayward south) works okay. Here are the best rates I can find (AAA or extended stay rate where available), before tax, for a selection of places. Rates are per night, sometimes averaged:
Ramada Inn: $124 Mountain View (close to office)
Country Inn: $116 Mountain View (closest to office)
Holiday Inn and Affiliates: $109 Union City
America's Best Value Inn: $106 Mountain View
Extended StayAmerica: $105 Milpitas
Hotels.com returns $96 for the Camino Inn & Suites, Mountain View
Vagabond Inn: $66 San Jose (10th night free, so effectively only about $60; however, it may require payment in advance, no changes)
Caravelle Inn & Suites: $70 San Jose
Motel 6: $60 Sunnyvale (Substantially closer to my office than where I am right now)
Motel 6: $46 Newark (shares a fence with where I am right now)
EZ-8: $43 Newark (where I am right now)
I think it rather likely that I'll try Motel 6 Newark next time I have a chance, as $3/night more is acceptable for a clean, comfortable room. There's no refrigerator, although I can finesse that if Lisa will let me take the electric ice chest.
A further complication is that on the next trip, Lisa will probably be with me because we want to take her to the osteopath again if we can. I need a better room in that case because she will be living in the room rather than just sleeping in it. Also, she hates shower-only hotels, so Motel 6 is out.