Around 10 k INR pp per day- if you have an avg accommodation and sharing accommodation with another adult. However, this would depend on a number of factors: What kind of accommodation works for you? would you be using public transport (i would recommend it) or private vehicle; Are you travelling in group. etc.
P.S. don' t miss the Mosque.
I would say 3-4 days for Dubai and a day or two max for Abu Dhabi (ofcourse if you wish to do Ferrari Theme Parks etc. - it may take longer). I had done a day trip to Abu Dhabi (which was okay because I was not into theme parks). Totally depends on what all you wish to cover.