How much to pay for childcare?

[NigellaTufnel]

DS's key worker at nursery is coming to our house to look after him (2.10) and ds2 (6 months) for about 3 hours one morning this week.

What should we pay her, as she has no hourly rate?

We live in a very expensive part of the London commuter belt, so rates for everything are high.
And she is great, so we don't want to take the piss by not offering her enough.

Any ideas? We were thinking £40.

To clarify... I think we are talking about 2.5 hours.

We have NO idea

I think £40 would be more than adequate!

I think £10 per hour would be completely acceptable.

many many thanks! think we will offer £40.

sounds to me like you are vastly overpaying her. I pay an experienced babysitter £8/hour and our nanny with 30 years experience is paid £10/hour. (SE London)

It's nice to be generous but if you want her to watch your children again you will be locked in to an extremely high rate.

i think £40 is fine if you are happy to pay £10ph - or if £8 then £32 etc

many nannies including myself have a minimum rate of 4hrs regardless if being used for that time,as often doing a 2.3hr job isnt worth it by the time we have travelled etc