Hiring a 4x4 for the whole trip will cost u alot.hire jeeps for places like minimerg from astire. U can take ur car to skardu frim deosai if u have a big heart. Otherwise not recimmended due to road condition. All areas mentioned in skardu are reachable by car though. So u will have to hire 4x4 from astire only for minimerg. U can do return trip through skardu jaglot road to save ur car from deosai road bashing. Skardu road too is under renovation and takes around 7-9 hrs