90g AGA tanks run about $250-350 depending on markup and whether they have a builtin overflow
Remember you want an appropriate stand for it - a full 90g weighs on the order of 1100+lbs. Store bought cabinet stands are fine, or you can DIY if you're handy with wood.
- Skip the wet dry or pre-built sumps unless you do not want to do any DIY work. If you're really not into minor DIY, a store-bought sump works, just is pricey. I would run them as a pure sump, so remove the bioballs and any filter media. Stick the heaters etc down there.
- UV is hardly needed in most systems, and unless it is a very good unit, won't be doing much. Save the cash.
- I would suggest a T5-high output light (one with individual reflectors per bulb), with at least 4 -54W T5HO bulbs. ReefGeek has good pricing on Sunlight Supply Tek fixtures. Premium Aquatics also carries Aquaintics fixtures (5 bulb). They look sleek and should be run without a canopy.