Looks solid, simple design, well thought out, why not? The assumptions can be evaluated only in 10 years. Find 500 € + / month as a student also already a very decent savings rate. Since some do not come here with full-time job. Of course, it's always individual, but to estimate times: about 50% of Germans put nothing back (except for saving for the next vacation or car).
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@KevinC at 500€ / month (plus hopefully at least inflation compensation) for eg. 35 years should provide for a more than adequate pension. Maybe you just think about your ideas and calculate what is possible under realistic conditions (e.g. 5% after inflation and tax). This will make the goal a bit more tangible.
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