Here's a list of the less expensive hotels/motels in San Francisco with the Mosser and Pickwick as comparison. They are probably about as good as any in this price range.
The only one I've actually stayed in is the TraveLodge in the Civic Center on Ellis. This is technically in the Tenderloin, but people who live in the area prefer the term "Van Ness Corridor". It's reasonably save if you don't venture any farther east of Polk Street.
It will be a challenge to find a room in a decent hotel in San Francisco for $60, but it's possible. It should be much easier to find one for $75.
Best Western, 364 9th St. at Harrison 415/621-2826 $76 or 800/780-7234, heated pool, free parking
Ramada, 1231 Market Street 415/626-8000 $79 between 8th and 9th or 800/227-4747 The entrance to the Civic Center underground public transit station is in front of the hotel entrance. Also, many major city bus routes run along Market Street in front of the hotel.
Howard Johnson's, 385 9th St. near Harrison 415/431-5131 from $79 or 800/I-GO-HOJO The Stud is next door. If you're feeling wild, Tranny (as in transexual) night is Tuesday night at 10.
Rodeway Inn, 101 9th St. at Mission 415/621-3655 $60 or 800/228-2000
Ramada Limited, 240 7th St. near Harrison 415/861-6469 from $49
Britton Hotel, 112 7th Street 888/511-5743 from $80 per night
Best Western Flamingo, 114 7th Street 415/621-0701 $69 to between Mission & Howard 800/780-7234 $109 pool privileges at the Americana. http://www.reservation-services.com/bestwesternflamingo.html
Bay Bridge Inn, 966 Harrison St. 415/397-0657 between 5th and 6th Several signs, including a billboard on top of the building, say BAY BRIDGE INN. $50/night weeknights and $60/night weekends with California Traveller Discount Guide.
TraveLodge, 790 Ellis St. at Polk 415/775-7612
$57-$67 or 800/578-7878
lower price with California Traveler Discount Guide.
I've stayed here and pronounce it adequate. The
rooms are small, and the management sometimes stingy
with heat for those of us from warmer climates. The
parking lot is fenced with a night guard. Sometimes
the sounds of street people yelling to each other
wafts into the rooms at night.
Econo Lodge, 825 Polk St. at Ellis 415/673-0411 $80. across the street from the TraveLodge $60/night with California Traveler Discount Guide
Red Coach Motor Lodge, 700 Eddy St. at Polk 415/771-2100 $69
Embassy Hotel, 610 Polk near Turk 415/673-1404 or 888/814-6835 http://www.embassyhotelsf.com/ from $80 per night
Comfort Inn, 2775 Van Ness at Lombard 415/928-5000 from $79 per night
Redwood Inn, 1530 Lombard near Franklin 415/776-3800 from $69
Ramada Limited 1940 Lombard near Webster 415/775-8116 from $78 http://www.stayanight.com/ramadalimsf/
Surf Motel 2265 Lombard near Pierce 415/922-1950 from $69
Super 8 2440 Lombard near Divisidero 415/922-0244 or 800/800-8000 from $65 http://www.super8.com
Econo Lodge 2505 Lombard at Divisidero 415/921-2505 from $68
Marina Hotel 2576 Lombard near Broderick 415/921-9406 from $75
Alisa Hotel 447 Bush Street near Grant 888/511-5743
3 blocks to Union Square
from $60 per night
Shannon Court Hotel, 550 Geary near Jones 415/775-5000
$86/night 2 and 1/2 blocks to Union Square
Grosvenor, 899 Pine Street at Mason 800/372-5570
4 blocks to Union Square
all suite hotel
From $79/night
Gates Hotel, 140 Ellis btwn Powell & Mason 415/781-0430 $49.95 shared bath 2 and 1/2 blocks to Union Square $59.95 private bath
Emperor Norton, 615 Post near Taylor 415/673-6718
2 blocks to Union Square
Single Occupancy with Shared Bath
From $50 (daily) plus tax
From $325 (weekly) plus tax
From $950 to $1,100 (monthly)
Single Occupancy with Private Bath
From $60 (daily) plus tax
From $425 (weekly) plus tax
From $1,200 to $1,350 (monthly)
Mosser Victorian Hotel, 54 4th btwn Market & Mission 415/771-4242
2 1/2 blocks to Union Square
Older building. From $70 per night.
2 persons maximum per room, no roll-away beds available. All rooms
non-smoking.
Golden Gate Hotel, $85-$130 775 Bush 415/392-3702
3 blocks to Union Square (some hills)
1913 Edwardian bed-and-breakfast on cable car line
afternoon tea.
Parking garage across the street offers rental cars.
Small, well-maintained older building (non-smoking).
Parking garage across the street.
Grant Hotel, 753 Bush near Mason 415/989-3239
$55 to $85 per night 3 blocks to Union Square (some hills)
Continental breakfast.
Well-maintained older building
Allison Hotel, 417 Stockton near Sutter 415/986-8737
one-and-a-half blocks to Union Square
$70 to $179 per night
http://www.allisonhotel.com/
Howard Johnson Pickwick, 85 5th at Mission 415/421-7500
3 blocks to Union Square or 800/227-3282
(south of Market Street)
$100+/night. Built in 1926 and featured in the classic novel
"The Maltese Falcon". Sony Metreon nearby.
Foley's Inn, 235 O'Farrell near Powell 415/397-7800
1 1/2 blocks to Unions Square
$75 to $125 per night
http://www.foleysinn.com/
The prices quoted are fairly old now, so you may get a better rate since tourism is down. Be sure to ask about any discounts or specials. Be sure to ask about surcharges, such as an energy surcharge or surcharge for a room safe. This costs often are not mentioned up front and are not included in the price quoted for the room. They often show up as unpleasant surprises on your final bill.