i've been installing steel ig pools in pa for 15 yrs, they are prob a 1/3 of the cost of a concrete pool,at least the prices in pa. the walls last a min of 30 yrs, liners usally last 12-15 yrs if u maintaing proper water chemistry. concrete has maintinence ,i believe they need to be drained every yr. they can crack,repairs and painting needed quite often. if i can help any more feel free to ask