well...we just returned from a road trip to uae, and it was awesome. (peace of cake if u have all ur documents in order and a well-maintained car)

First u need to check if u r eligible to enter UAE (visa on arrival)depends on ur designation on ur passport (Doctors/Engineers/Managers/Deputy Managers etc) check with the UAE Embassy in Doha though - if you are not eligible, then u need to apply for a visa to uae (NOC from your company)

Then u need to apply for a saudi transit visa (which is usually obtained through an agent {around QR. 135/- per passport)check with ur mandoob - which takes about 3-4 working days.

The driver of the vehcile need to carry the vehicle documents, mulkiya etc.

There is Insurance to be paid on the saudi border and UAE border of QR. 100 /-& QR. 70/-

At the UAE border you need to go to the arrival lounge to fill in the forms for visa (visa upon arrival) QR. 100/- per person, and then you need to get your retina scanned

(For GCC Nationals, the formalities are relatively less)
Make sure you retain all the slips etc, till you return back, you also need to give these slips back at the UAE departure with a fee of QR. 35/- (EXIT FEES)

Make sure your tank (gas) is always full, and fill it up at every chance you get (Gas is cheap in saudi)

Adhere to the speed limits etc and you should be in abudhabi in about 7-8 hours.

HAPPY DRIVING!!