You could check availability at Suites at Fisherman's Wharf.

http://www.shellhospitality.com/en/The-Suites-at-Fisherman-s-Wharf

http://www.tripadvisor.com/Hotel_Review-g60713-d247005-Reviews-Suites_at_Fisherman_s_Wharf-San_Francisco_California.html

I wouldn't say these "cater to" families, but there are several motels in the Marina/Fisherman's Wharf/North Beach area that are often recommended on here. Look up the Cow Hollow Suites and Chelsea Motor Inn. The advantage to being on Lombard Street is the proximity to Union Street (not Union SQUARE, Union STREET) and Chestnut Street, both of which are awash in restaurants and shops, everything from sandwich and breakfast places to higher-priced restaurants.

Here's a link - before to click the link under "Sister Properties"

http://www.cowhollowmotorinn.com/

Thanks for the suggestions. Am a little worried that all the decent places will be booked up as we did not realise that is spring break!

I just checked random dates (Apr. 4-7) for a family of 4 on Expedia, and just about everything was sold out. So I agree with you, get on it, and quickly!

Those same dates (Apr4-7) Hotwire shows Fishermans Wharf 3* Boutique, two adult two children for $129.00. Probably Best Western Tuscan Inn, not a bad place and i would say good value. I realize FW is not a fave with the Fodors posters, but I thought it was great when I was a kid. Can always take the cable cars to Union Square.

Dave, if you put in the correct number of people, i.e. two adults and two children, it's actually $159 plus fees - $188 per night. It still might be a good idea, but it's not as inexpensive as suggested. At least it's available!

We have gone down the apartment rental route and have booked now. It works out cheaper and will be nice to not be in a hotel for a couple of nights. Thanks for all the information.