For this price range check out Obris Morgan. Very limited supply when they're released but excellent reputation and I love mine. Gets more recognition than my Tag.
Gas heaters will cost you about $100 to heat for a weekend.
Heat pumps are significantly less to operate but cost more up front, figure 40+%. Kick in another 15% for a heat/cool model. If you want to heat for christmas and it's really cold the heat pump wont work effectively below ~40 degrees.
In Texas just make sure you use hayward, pentair, jandy or aquacal. There are other manufacturers but they don't have the support in the market if something goes wrong.
The CYA stabilizes the chlorine so it isn't as affected by the sun and burn off. Typically is salt pools you want to keep CYA levels higher as your not adding more in with each dose of tabs.
Tab pools you want lower, i try to keep my pool closer to 30 ppm. A high cya level can lead to chlorine lock, which is no bueno.
I'll second the robotic cleaner with one caveat. Polaris has been around forever, parts are everywhere (and knock-off parts made by CMP generally work well and can be found online). When your robotic dies, unless its under warranty, it is a lot more expensive to repair.
If you find the right house with the right pool, buy it. If it isn't too old you're not likely to have many issues. Have it inspected by a pool guy. Not just the home inspector.
Most are made by one of two manufacturers and then the retailer or builder buys them through distribution. So its not like academy buying a truckload at a time. Every company that buys marks them up. If you get one online you can probably save some $ but make sure that the post, or posts, will fit into the anchor(s). Most of the posts are 1.9"OD.