The apartment was initally difficult to find: the driver couldn't even find it on his GPS! After searching for nearly an hour for the property, I discovered it was at the top of a very steep hill. With no clear signage for the property, and the numbers of the houses on each street being inconsistent, it made this even harder to find (even a native of the neighbourhood couldn't find it). After finally finding the apartment, I realised that the walk to and from Mlini each day would be considerable.
The owners were lovely but spoke little English, which is fine, but fundamental questions could therefore not be answered (departure procedure, use of the kitchen, laundry facilities, etc.) and I wasn't told about them due to the language barrier. Luckily Petar was contactable via email if there were any problems/queries, all of which were answered swiftly.
HOWEVER, my room was clean, tidy and comfortable. The views were spectacular and it had all the amenities one could wish for for the price I paid (fridge, on-suite, balcony with table and chairs, air-con, TV.) Petar was informative about excursions, things to do and recommendations when going both to Dubrovnik and Mlini. Nothing was ever too much trouble!
Overall, it was very pleasant and I had a great time. A car is advisable but not a necessity. Just keep in mind its location and distance when booking.