Maintenance costs are minimal with saltwater pools. As long as you keep your levels correctly you can get away with a couple of hundred/season or less in chemicals. Also it costs me $300 to have the pool professionally closed in the winter. To go a little larger is a negligible amount of additional seasonal costs.
For your size pool I think you need a 3hp variable speed pump. Single speed and variable speed are frequently the same net price due to utility rebates on variable speed pumps ($400 for me). Any water features? Are you going to heat it? I would also price out gunite/plaster pools. Are you getting automation?
No water features, I did get quotes for gunite which was around 50K, same specs for a 42X20 concrete liner pool without heater, I was quoted 29K including permit fees + engineering drawing etc,
I didnt opt for any concrete work as I have my own paver mason who has worked on my patio and other masonry work around the house.