Financing plan with transitional housing

Hello,

I have the following idea and am asking for advice:

My parameters are:
I currently live in a rental apartment with 500€ rent (together with my girlfriend)
With my salary, I could comfortably set aside 1200€ for a monthly investment independently of my girlfriend if I didn’t have to pay rent. Savings so far: 25,000€
We are both tied to our location for the next approx. 3 years (current location city differs from the target location country).

Since we don’t want to throw our money out the window through rent and also want to save equity for building a house, here is the following plan:
We buy an apartment for max. 100,000 Eur. For this, we need a loan. We will live in it for the next 3-5 years. When half of the apartment is paid off, we sell it (assuming the apartment is sold for at least the same price as it was bought). With the money saved during these 3-5 years (now available as equity), we then take out a larger loan to buy a house worth, say, 250,000 Eur.
The idea behind this: accumulating equity by shifting rent into investment and additional monthly savings.

Does this make sense? I would appreciate advice and pointers on problems or optimization help.
Building the house is, of course, the top priority.

Best regards

Where do you save money with that? You have additional purchase costs, there may possibly be repairs to the house at exactly that time that you have to share. And the loan installment plus [Hausgeld] will probably easily exceed €500.

As Robin says: Purchase ancillary costs are wasted. Also the prepayment penalties. Result: +- 0 Renovation and moving costs on top again. Rent is never wasted money because you get something for it: the living out of a property. Best regards in short

Rent is never wasted money because you get something for it: living in a property.

What one, in my opinion, forgets in this context is one thing:

With ownership, you do something for your future and children. If you take care of your property, or later rent your condominium to your children, the balance in my opinion clearly tilts towards the positive.

So for 3 - 5 years, you burn more money than you gain through appreciation.

The idea is just really bad :) Simply "Don’t throw rent out the window" shows me that you still have a lot to learn. Save up some equity first (25k is not really much... practically almost nothing). Regards, Steffen