The problem i can see here is you are using 1 tote to get your results but favs can be subject to interstate fluctuations.

You may be looking at a horse that is listed at $4 pp and come race time may be $3 Stab but $2.50 NSW so it is a bet in one state but not the other.

Try importing VFG real time prices in to your excel sheet this will provide you with all 3 tabs plus betfair place prices.

You need to decide what horses have firmed but then place your bets at the best price.