Book Keeping Set up and Advice

Hello, we run a small sized building and property development company. We need someone to put our financial administration into line. The two partners have no training in this area and are looking for guidance. We would like to set up a system based on a sage package that we can then take over for data entry when the system is up and running. Effectively we need someone with good experience to advise us as to how to get our books in order and then maintain them! We imagine this will take around a week to achieve. We are clearly open to suggestions form the right candidate. We are based in South West London.