Croatia by car

Haven't rented a car but May is not super crowded except for cruise ships groups, so you should be okay.
I would go ahead and research different companies though--if you are planning to take the car to Montenegro or Bosnia, as you'll probably want to compare the rates for doing so.

Should be no problem - there are thousands of rental cars along the coast ready for high season, so you'll have plenty of choice and may get a good deal. Go with reliable local firms rather than the big boys and it can be quite affordable. There's a list of rental places here. Gulliver's website for instance mentions cars from 46 euro per day, Uni-Rent even from 27 eur/day.

I think that is cheaper book online ... then when you coming in Croatia because our local prices is 30% more then standard in europe... so our company must sell cheaper on on line production

hi, you will have no problem getting a hired car, there are several car-hire agencies to choose from.
compare prices and decide:

http://www.kompasrent.hr/

http://www.dubrovnik-rentacar.com/

http://www.dubrovnik-online.com/english/rentals_booking.php

http://www.carhiredubrovnik.com/

http://www.mack-concord.hr/english.shtml

http://www.brabel.hr/eng/home.htm

Thanks that's really helpful!

Be aware of 22% PDV local tax which some Croatian car hire firms do not include in their on-line quotes. Try these International firms, they are the best we found for price and service.

www.economycarrentals.com

www.auto-europe.com

Thanks everyone!