OK, in case anybody wondered and to close this little story off:
I have by the end of February returned the car to Kobi. Except for the last at which I incidentally also had to get my kids to POP airport the car performed flawlessly. As the devil is in the detail, the people of Kobi where abroad in Santo Domingo and asked me to seek technical help since I speak Spanish. Half of downtown Puerto Plata helped push the car to a shop a couple of blocks further, which slightly dammaged the front of the car as they ran me with all the well meant energy into a ditch they could't see from behind and I coudn't break without the engine. As I did not have the time (trip to the airport) I left the car there without asking too much. The next day Andre of Kobi came to pick me up at my rental apartment in Sosua, which I was also suposed to vacate that day and generously helped me move my stuff to my new location in Puerto Plata. Then we drove to the shop. They paid for an over priced repair bill without coment, for which I felt a bit ashamed (I should have done better, and would have if I only had had the time) and we drove back to their location in Sosua. I was refunded my deposit without any hassle or discussion even though they where not too happy about the damaged front spoiler.
As if this wasn't enough, they apologised for not having being able to be of assistance that particular day.
Bottom line, as I am not allowed to recomend them here on this forum, I will just say that I would use them anytime again.
... J-D.