Hey Allen,
The zero safe idea for sells is copied from Tom a couple of years ago with the idea of decreasing the span between buys and sells, and allow the opportunity to gradually let go of higher priced shares and pick up additional lower priced shares as the program churns up and down at the bottom...gold and silver stocks have been a good example the last six months or so.
I use the Aim Calc to determine sale price with 10% minimum. Not set on lower priced companies. In fact, attempting to move to more quality dividend paying companies as value opportunities present...watching OXY, COP, CVX, XLU etf and others for entries at or below 33% of 2 year high if presented and companies sustain good fundamentals. For Aiming a portfolio with less than $100,000 I start each equity/Aim program with $6250.00 ($5000 stock/$1250 cash or 80/20). This gives opportunity to provide for multiple industry involvement and diversification. Just a matter of being patient and building a quality Aiming portfolio and ultimately reducing cost basis through Aiming buys and sells, and dividends to result in profitable outcome over time!
Alton