Nice to see some sensible replies for a change and no A vs B nonsense.
I would like to add a few comments to the excellent ones already mentioned.
The guys are right. Please do turn off the water supply to the water heaters.I have heard too many stories of colleagues coming back to floods and wrecked belongings.
Also, great idea with the power supply as well.
Do yourself a big favour and go to the RSA stand at EGHQ and get a contents insurance policy. I think 50000 AED cover for EK staff is around 250 AED.
Also, LOCK all the internal doors and put broom handles in the tracks of the patio doors.
Finally, you could trip the breaker (inside the house) for the garage door if you have one as this can stop any potential thieves getting in and loading up unseen.
Sadly, villa break-ins are quite prevelant.
Hope I don't sound too paranoid!!
Have a great time away.
All the best