Friendly Economics ?
Owning a € 20-30 K C152 is unlikely to provide a maintenance budget that you are looking for............ I know I own two of them ! They are used in a long term lease to a training company and both have just been through the SID's at a cost of around €20k, these aircraft were always considered by my customers to be good clean aircraft so it is anybody's guess what an average C152 will cost to maintain properly even if you only do the SID's items that are critical to flight safety.
So to get an average C152 to a state at which it will meet your annual maintenance budget it will cost around €45K and another €25K to put a zero time engine in it.
Or you can look at this particular DR400-140B, it will meet your annual maintenance budget for the next ten years, is a much more capable aircraft and I am guessing will cost around €80K, the economics are such that it is worth borrowing the extra money as it will be cheaper in the long run than taking a gamble on an airframe that may have hidden problems.
Unless training is your mission the C152 is not for you because that is all it does well, you will find that you will want to do more than just fly locally and you may also find that your dogs will fit in the back seats of the DR400 !