I also see it initially as unproblematic and feasible. But you need to decide quickly whether and when the apartment will be sold. This will also determine how you want to structure the financing.
Again on the topic of equity: You will have to cover the additional purchase costs yourself or borrow them at very expensive terms. Therefore, the tip is to better include everything and add the same amount on top to the financing.
If you really expect expensive surprises during the renovation, directly order a higher mortgage to be able to finance additional costs. Feel free to discuss this topic with the advisor.