You had a conversation months ago with financial experts whom you still know. Since then, however, you haven’t saved any equity capital of 0 EUR? Or do you now want to save 5-10? When would the transfer of ownership be?
As a rule of thumb, one says 5% p.a. for repayment and interest. That means, for 365,000, you should be able to raise 1,520 EUR already.
Besides, your project seems to be calculated quite tightly.
For 300,000, I alone come to about ~32.5k€ ancillary purchase costs. So 32,500 should be enough for renovation and furniture, and what else? I urgently recommend you to deal with modernization/renovation costs today.
And what reserves do you also want to co-finance?
Have you thought about approaching your specialist?