Some Brokers do not provide all Asset Parameters via API, such as Oanda & swap (Rolls). The manual says to find these figures on the website, but that's not always easy/possible, and websites have this annoying habit of getting out of date.

Another approach could be to sample the Assets (e.g. for Oanda via script in another thread) and see what values result, possibly doing this a number of times and averaging?

If this latter approach is used, what would be a good sampling frequency over what time period? Hourly for a week? A month?

And how often should it be redone to reverify the averages are still good?

Thanks.