At a minimum, you should plan to contribute at least the transaction costs from your savings. Keep in mind that property transfer tax, notary and real estate agent fees can amount to ~10-12% of the purchase price.
As long as these transaction costs are covered by you and are not financed by the bank, the likelihood of getting a mortgage approved increases significantly. Every Euro that you invest on top from your savings will decrease the monthly rate and also improve the interest rate.
The rule of thumb in Germany is to finance only 80-85% of the property purchase price and cover the rest by equity. Feel free to consult our experts free of charge for a first consultation on your real estate financing in Germany.