A banker will always ask his clients to put in a deposit. It's normal; he likes security. He seeks to minimize his risk.
Unfortunately, too many clients settle for that.
On the other hand, every day lots of home loans are granted without a down payment, simply because the customer has said "no, I won't make a down payment".
Everything is negotiable. There is no universal rule.
If your file is good and your project is good, there is no reason for a bank to require a contribution.
You have to know how to present things, i.e. show the banker that the project is viable and low-risk.
And you have to be able to make him understand that if he wants to keep you as a client, he has to make an effort. Otherwise another bank will do it, so that you become a client.
Your savings are your bargaining power. It's better to bait bankers with your cash than to spend it on contributions.
Everything is negotiable, everything is argumentative. You are the master of your project. Show that you have a beautiful project, that you are serious, that you know what you are doing, and go around the agencies.
Two branches of the same bank may receive you in a totally different way. It depends a lot on the personality of the advisor, and his or her desire to build a credit file. Some people just don't feel like it, so they find excuses such as demanding a contribution.
Real estate millionaires get around that.
Good luck for business.
You are right. With a good project and ability to convince the lender that you know what you are doing, the deal can be sealed.