hi ive been selling on ebay on my dads account for the last 2 months now and ive been making about £300.00 a month and its on the increase, ive been looking on the web and to get cheaper stock you need a VAT number and to get A VAT number i need to be a bussiness or could i just do it as a sole trader. all so what do i need to do to trade under a name rather than my name

ps. i live in the UK and im 15