Transportation

In general an expat cannot own commercial pick up vehicles; except in special circumstances, or if owning a business.  To ride a bike, you need to obtain the bike driver license.  Yes there is a test.

i currently own a car in saudi. if i drive it to dubai. how long can i get away with just keeping the saudi plates? will i have to change it to UAE plates? what is the process of getting UAE number plates?

No dear u dont need to change saudi plates. U can drive the car with them. Just u will need visa to visit uae and via road u can enter uae via saudi-uae border.

how about car insurance? for lets say a 2006 mustang?
and expected monthly transportation expenditures??

By transport expenditure u mean petrol exp? And insurance for mustang from saudi or from here UAE??

a friend there will sell me his in case i dont bring mine over from saudi. yes, i understand gas there is more expensive. so i want to get an idea.