Room to Rent in friendly family home

I have a slightly chaotic life, which involves lots of theatre, music and pottery, as well as some light teaching, so I'm always busy, but always poor! Just have one of my three sons living with me at the moment (he is just coming up for 20) so there is space to share.
The room has a little sofa in it, and is a nice place to be, but you are welcome to use all the shared spaces in the house, including the garden, which is a great place for hanging out and enjoying a barbecue.
The house is opposite a common, and there are a lot of woods and green spaces around, but it is only a 10/15 min walk down to Plumstead Station or a 10 min bus journey to Woolwich, where you can catch the Underground and Docklands and get into town very quickly.
Couples would be considered for the room, but I would then have to ask for £1000 a month to cover the extra bills.