Nicole:
For starters, please add your signature.
It is extremely difficult to answer this question without knowing your pool, type of cover, dimensions of the pool, your surroundings, the cost of water, type of structure, your past experience, etc., and why you are asking this question.
I have a friend with a 90,000 gallon pool. The safety cover cost $13,000. After a few years, it ripped and was deemed useless. Since then, the pool is closed for the season & not covered. In the spring, the pool is drained and refilled after a thorough cleaning. As you can see, a liner pool could never be accomplished this way, but a concrete/gunite pool can. Please advise. Thanks!