HI lou You can have zero REAL shares if you would like to buy a stock but only if it goes lower. Setting PC to twice what you own works well but if you go much higher you are likely to run out of shares. But that is your choice. You should alter Aim settings slightly 5% buy and sell safe, 10% minimum order size, PC IS PRETEND AMOUNT OF STOCK. I increase BUY SAFE 5% with each BUY up to 20% maximum and reset back to 5% when I have a SELL. Toofuzzy