Yes , all ISRO employees are eligible for getting quarters but it depends on the vacancy of the quarter. In some Ahmedabad center of ISRO , the quarters are very good with higher capacity of accommodation.

ISRO provides great quarters for their employees but it may take some time if their is some scarcity. If there is no quarters available they will provide HOME RENT ALLOWANCE so that you can rent a room for a period until and unless their is quarter vacancy.

Also there are some special provisions for Women employees if they are not the domicile of the state in which they got selected , then they may get some extra benefit of getting a quarter.

I hope my answer helps. Wish you a prosperous career ahead!