Hi. I have used a system "Quick Books"barclays bank offered it to customers (some commission tie in no doubt)but i works for me. Keeps track of invoices, suppliers invoices, vat and who has not paid. As well as allowing cost codes to be set up for fuel, motor expenses, insurance, wages etc. At the end of any time period you just print out profit and loss sheet and let a accountant work out your tax liability. Go Luck