Your slippages depend on many factors like the selected strike, market volatility, liquidity of instrument, bid-ask spread etc. Generally you may assume at least 0.5% slippage for option selling and 1% for option buying.
How to solve it.
If I have Nifty strategy of 4 options leg and Target is say Rs 500. When I execute in live market when exit triggers on achieving target (say 579) but when executed it shows Rs.-125.
How to tackle this slippage
Option buying in BANKNIFTY deep In The Money 500points
To tackle slippages use Limit Orders for entries and exits with a buffer not less than 3 points.
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