Single Mom needs overnight supervision of older children while away on Business

I am relocating to Roxborough Village, Littleton, Colorado in October 2005 from the UK. I have two children aged 15 years and 12 years and a toy poodle named Charlie.

My job takes me overseas quite a lot and will do probably more than ever in the first few months after we relocate.
What I am looking for is for someone to come to the house at about 7pm in the evening, cook a simple meal for the children, stay overnight and make sure they are up for school next morning. As I said I will need this on a pretty regular basis to begin with as I will need to fly back and forth from the USA to the UK.

Is this something you could help me with and if so what would be the estimated cost of this service?

I will also require a cleaner 2 hours a day 3 times a week