Arbusers

1. How much time do you need to place a live bet?(In your experience, how much time does a live arbitrage needs to last?)
For example, if i place a bet on team A, it takes 10seconds to place it, but only x seconds it takes to validate the bet. (Do you know what time it takes to validate the bet? i dont need site name, i just wonder if you know, and how much time it takes)

How do you know how long it will last?(only with statistics i suppose)