These savings include 800-900 euros that are currently paid monthly for loans, so we have basically always saved that amount since it has been deducted from the account for years. Additionally, we have always saved 700-1000 euros, which then went for vacations etc, which with the house will definitely be postponed for now.
Therefore, I don't find that unrealistic. That's not a full additional 1,500 euros. I think many here haven't understood that yet.
Somehow I'm slowly getting tired of writing here. According to your first posts, the loans are not yet paid off. Subsequently, you wrote that you now want to try to pay off the loans as quickly as possible. Ergo – you are not yet saving these 800-900 euros and in the next few months you will not have them available (until everything is paid off). Yes – you had written that you set aside a sum X monthly for vacation/consumption, which then was spent exactly for those reasons. So one could count this as savings IF you actually left it untouched or decided not to go on vacation anymore / reduce your consumption. Alone – with your previous lifestyle I lack belief in that. This is not bad. Many people find it hard to give up beloved things (once again, a nice vacation). But if you want to take out financing and do not have funds available elsewhere, you MUST draw that conclusion.
You're not the only one feeling this way. Last year, after building the house, we took a "vacation" of 4 days – 2 days of which I still had a training session. This year we will go to Munich together for 4 days. Otherwise, our "vacation" consists of visiting the parents. I myself increasingly long to go back to Norway or to the sun. This will probably continue until our outdoor area is finished (at least another 2-3 years). But we had already learned earlier, before financing, to do without in certain situations. You haven't had to so far and never did. You have to first prove to YOURSELF that you can and want to do this.
By the way, I do believe that you could get the financing because you do not appear to the bank as (informatively) as you do anonymously on the internet. But how it might look in 5 or 10 years, if you don't manage to give up old habits, ... .