We stayed here is Split https://www.airbnb.co.uk/rooms/3389889
Very close to the old town/everywhere you want to go in Split, literally 3-4 minutes walk. The unit itself was fine, the bed kinda sucked but then again, all the beds were pretty shit - we just dealt with it. It is ground floor of a 3 storey rise. The host was lovely, had local wine for us etc.
If you go to Split, hire a car and go to Krka national park. You can park and get in from Lozovac. Alternatively, you can shuttle to the park. They will most likely take you to Skradin, which is beautiful. There is a boat that will take you up the river - all inclusive with the ticket to the park. I think most tourists see Krka this way. We'd hired a car already so we ended up in Lozovac. The park is beautiful though, don't miss it! If you hire a car, drive back around the coast from Sibenik. It is incredibly beautiful, one of the highlights of our trip.
Ok i have to recommend this restaurant in the Old Town. Host was briliant, menu is simple and reasonably priced but the food is all incredible, fresh, handmade etc. Definitely get the rabbit pate as a starter. We ended up eating here twice. I don't have a name but here is a google maps link; it's very easy to find https://www.google.co.uk/maps/@43.508706,16.4396026,3a,90y,312.21h,70.41t/data=!3m6!1e1!3m4!1sovJpmNMnahlYyH98EfeVZg!2e0!7i13312!8i6656!6m1!1e1
My girl STILL brings up the pasta dishes we had here one night :)
Hvar island was also incredible however we went to the old town (Stari Grad) which is a lot smaller than the other side of the island.
Dubrovnik: https://www.airbnb.co.uk/rooms/3549745 This place was cool, not as conveniently located as our room in Split was but definitely the nicest unit we stayed in. This guy owns two buildings, four units in total. He lives in one and Airbnbs the other 3. This one had the best bed out of our trip. Dubrovnik was very cool, I highly recommend checking out the Elaphiti Islands - Go to Lopud Island, bugger the other two. It is beautiful and Senj Beach on the Island is gorgeous. Nice sandy beach, NO SEA URCHINS! We ended up doing this twice as it was very easy, boat fare is cheap and a quick journey, very relaxing. The old town is a must see of course and head up the cable cars for a wicked view of the city.
Pula is awesome. Quite a bit further up the coast however. I've been recommending it to a lot of people - far less tourists but still a lot of cool things to see and do.
If there's anything else you wanna know, let me know! Happy to help.
Have a good trip! :)