Dear,

If u r alone need 1000 riyal for your food and personal expance depands on your desire. But need 5000 riyal per month of you r alone then u can save some money.

All is depends on you that how much u r going to spend. also what position and which type of job you r doing considering your experience.

Atleast 1000 for bechlor and 2000 if with family are minumin expance.

Hope u understand