We do ours every three or four weeks. I prefer to take a little bit off but do them often so it keeps them in the habit of getting their nails trimmed.

Jasmine is good and only takes one person. Mini used to be a devil and needed to be wrapped in a towel with two people and plenty of scratches, but now I wait until he's looking for attention and pet him while I do one at a time. Takes longer, but it's less stressful for all of us. I do Tabasco while he's asleep and Pickles is one claw at a time while I'm petting him. Luckily I don't usually need to do the back feet as I'd be there all day!