@buzzard I think the big problem is that you have too many things. Not just the amount of debt. The number of different things is causing you stress also as you are having to juggle them all.
Taking your list:
Bank1 Loan - Outstanding balance: € 12.000 @ 10.9 % (monthly repayment 386)
Bank2 Loan – Outstanding balance: € 200 @ 13.4 % (monthly repayment 105). Final payment end of November
Bank3 Loan – Outstanding balance: € 1800 @ 0 % until Feb'24, 20% afterward (monthly repayment 100).
Avantmoney – Revolving Credit Card – Outstanding Balance € 7000 @ 20% (min repayment 180)
Foreign Credit Card – Revolving Credit Card – Outstanding Balance € 6500 @ 18 % (monthly repayment 210)
Bank1 - Agreed Overdraft € 2500 @ 15%
Bank2 - Agreed Overdraft € 1000 @ 15%
You ideally want to add another 6k to your Bank1 loan. Then use that to pay off - Bank2 loan, Bank3 loan, Bank1 overdraft, Bank2 overdraft. Then cancel Bank2 overdraft facility.
So you are now down to:
Bank1loan - €18,000 - monthly repayments the same, €400, just repaid over longer time period
Avantmoney - €7,000 - existing repayment €180.
Foreign Credit card - €6,500 - existing repayment €210.
Instantly thats now vastly easier to conceptualise. You only have to keep track of three repayments a month instead of seven. You also have the backup of the unused overdraft with Bank1 in case things go wrong. Plus you are making €200 a month less in repayments.
That €200 a month needs to go only to AvantMoney. You need to focus on one debt at a time and learn the joy of seeing it being paid down. So now rather than just paying off the interest on this you are seeing it actually fall. Try to get the monthly repayment on this up towards €700 - so scrounge up a few hundred extra from somewhere. Your income should support this. If you moved into shared accommodation you would have this up over a grand in monthly repayments and its fully done and you're on to the second credit card before the summer of next year.
Consolidate then pay off. Good luck!!