Greetings. Where in Europe?
As for can it be converted? Maybe, depends on how much money you want to throw at it. To me trying to convert is a big nono. However you could easily enough add a small water tank, a small holding tank and a couple of bunks with storage under for camp stove, chairs etc. You could do this for a few hunderd, euros in your case. My brother did a couple he used for fishing trips alone or with one other for a few days. The last one worked really well.