Hi, I have about 30K in my Interactive Brokers account where 25K is tied up in equities already leaving 5K of available funds. My algorithm has 10 equity symbols to trade and it uses the following method:

 SetHoldings(equity.EquitySymbol, 0.10);

I assumed that this order would be 10% of available cash allocated to this symbol so $Price/ $500  = quantity bought. However, it tried to by ~3K of the first symbol on the list (which is 10% of the total equity not available cash) and other orders were rejected due to unavailability of cash so it looks like that is 10% of total equity allocated instead.

Am I doing something wrong? Is there a different way to do this? For example, I can find the amount of available cash then calculate the percent allocation based on the price?

Any suggestions would be appreciated