I live in west london and I see plenty advertised but have not met anyone who has tried them. I have only ever had one friend to babysit (not through choice but no one else has ever offered!) But I am planning to get married next year and although we are doing this whilst on holiday we may be having a sort of reception/party later to celebrate. I would want my friend to come so have though of using a service but leaving my son with a stranger that I haven't established a relationship with seems very odd. Anyone here done it. Was it ok? How much does it cost?