Now I'll play bank:
Income: €6,500 monthly (assuming you can prove that the mini-job is sustainable and long-term)
Living cost flat rate: €3,250 monthly
Car loan: €475 monthly
Remaining for a payment: €2,775 monthly
For a 100% loan-to-value (so according to my calculation a loan of €420,000 we would currently charge 3.65% interest and 3% repayment).
We would reject the financing at the amount you requested – just so you know.
Now to the asset situation:
Asset estimate: reserve €20,000 on the credit side
Liabilities estimate: car loan €50,000 on the debit side
This already involves a manual review of the financing request with us because the customer is over-indebted.
It will be hard to sell that to the bank – a fancy car and no money for it, but wanting to finance a house to the max.
What reasons should a bank have to finance you? You can barely afford the payment, you are over-indebted and a career starter.
I wish you lots of luck, you will need it. Not to mention all the other issues with the property (valuation, photovoltaics, energy efficiency, already 25 years old, etc.).