I have seen your post, and while unfortunately I'm not available as a nanny, I also live next to Wandsworth Common, just off Northcote Road and am looking to babysit locally on evenings.
If you ever do need a babysitter, please do get in touch. I work full-time during the day but am usually available from 6.30pm.
I have experience looking after children of all ages, and would be happy to go for a coffee if you would like to meet me.
Have a lovely day!