Write off depts/credits of members

[marcelb98]

Some members cancel their membership and leave their account with debts.
Over the years those debts accumulated to a quite high amount of money which we theoretically could collect from those former members (which is listed in our accountancy).

To get rid of this big position, we should write off those old debts.
To do so, the user account should be cleared to zero Euros by creating a transaction to some kind of expense account (”Beitragsabschreibung”).

The same applies for positive credits users have on their accounts long times after cancelling their membership.
According to our Beitragsordnung users have to request a refund withing 31 days.
Taking into notice that some people cancel their membership for a semester abroad, we should keep their credits for at least 6 months.

Legally users have no entitlement on their credits 3 years after 31st December of the year they cancelled their membership.
That's the latest day we should clear the users account to zero Euros with a transaction to a revenue account (e.g. ”Spenden“, maybe we want to create a special account for that case?).
I would suggest using this timeframe for both directions (debts and credits of users).