Hi Sylvia. Just noticed your post. Hope you are well. I did this trip with a couple of friends in June. We went from Heathrow which necessitated an overnight at the Premier Inn as check in was very early in the morning.
Lovran, where hotel is situated, is about two hours away from Zagreb so you would have to include this into your travel time if you went via Schipol.
Hotel is quite large and is popular with families in local holiday times. Rooms were fairly large and comfortable. We paid extra for sea view rooms and were glad we did. Front rooms faced onto a busy main road.
I enjoyed the holiday but have to say that I preferred my previous one to the Dalmatian Coast.
Hope this helps
Lesley