hi, i am in a similar predicament, though i havent gotten the formal offer yet. i did a bit of research using the following:
1. getting the relative rates of the same position (and pay) compared to my home country (philippines). you may check www.payscale.com for this info. the job will not be exactly the same as your job description but im sure you can see which one is the nearest to your job.
2. get the information from friends in the same company who have knowledge of job grades and pay scales
3. ask around for the acceptable 'manager' wage based on people who have been in UAE long, im fortunate i found someone to give that info.
All told i was able to see that the pay range for the job i was looking at should be in the range of 4000-5000 USD based on those three information. so hopefully i'll get the higher end of the range when i meet with my potential new employers next week.
i hope this helps you.