Financing outdoor facilities, carport, equipment

With your amount of equity and the short fixed interest period / term, you should get top conditions for the real estate loan.

As a banker, I always give a defensive condition in such constellations!!!

Anyone who calculates commercially (unfortunately, it is often better for the customer that this is not done) may only offer such financing with really hefty surcharges. Why? Short capital commitment and small amount = extremely low returns and very high (relative) costs. Let the bank maybe earn 0.20% on the financing - that's 250€, from which all the costs of the financing have to be covered. Even with automation, that cannot be profitable. Especially if there is also a broker involved who gets a 1% commission.

But whatever, some banks are just that crazy...

Or you find friends, family, or similar who currently have too much cash and take out a private loan with them.

So I would have taken out 100k-150k now for the house. Equity then for the outdoor facilities. If you still have a few thousand in reserve for all eventualities of life, that's not the worst...

Ditto. With excellent creditworthiness and the current interest rate level, I would never sink my savings into real estate. Just discuss with the banker what is best. Maybe take out 200k, leave a buffer in the daily allowance account, and put the rest into ETFs. There should probably be more in ETFs than the measly 0.9% you have to pay. (KEINE ANLAGEBERATUNG)

For the stock market, however, you need a certain risk tolerance. Acquiring it right away with several hundred thousand is the very tough way. Also, we don't know what time horizon is planning for. There are people who build for retirement and have their own capital from the sale of the previous property ;)

I would also advise you to arrange a traditional construction loan now. But even so, you have a very, very good starting position. Is the Kfw loan currently not secured in the land register? That could pose a problem if the bank goes into second rank. Then even a consumer loan is competitive.