From my experience and having a pool in just about every home over a long career and many moves:
Those "heaters" will make your energy bill zoom into the stratosphere!! Swimming until Thanksgiving sounds great until the bill for those cool months more than doubles for heating the pool. Yeah, sure - gotta do it - but beware of the associated cost. The further north one lives, the shorter the swim season and the less practical a pool becomes.
One solution to the heater issue is to have a "hot tub" associated with or connected to the main pool body with the heater and return just in the hot tub area which will reduce the volume of water heated and thus reduce the amount of energy required to keep an area warm for a longer period of time. Overflow/water fall into main pool of course. Just pipe it so that you can isolate the hot tub seasonally as necessary.
I also found that a pool service company appears expensive - until you start buying all the chemicals and tools you believe to be necessary and spend an inordinate amount of time "getting the pool ready" before you jump in. With a pool service, the pool is ready without the time lost messing with it.
Put a fence, post a sign, etc., even if your city ordinances don't require it. A child (or neighbors pet) wandering into your yard and falling into your pool with or without supervision can become a liability and legal and insurance nightmare!! Some cities require a fenced yard and in addition another fence just around the pool itself (this happened to us in Austin)... Double protection. Pools are magnets for kids - just beware!! Check your homeowners insurance policy to make sure you are covered!! Gates with "adult latches" or even locks will give you some peace of mind in this regard.
Pools under or even near trees and shrubs and flower beds - even grass too close without adequate walking areas around the pool, etc., are just an invitation for leaves and clutter and even insects to be a mess in the pool. The more "open" the space the better. If near the house - connect patios, etc.. with pool deck and avoid strips of vegetation requiring maintenance and pool clutter.
The point above about "contingencies" - i.e., other piped utilities, soil to rock blasting, access to site, fence removal and repair, drainage issues, liner pool or gunnite, location of pumps/filters (and exposure to open air without protection), deck treatment, slides/goals/nets/waterfalls, site and landscaping development, etc., are all incidental "additive cost items".
Lights in pools are beautiful when installed correctly, but the slightest damage or poor installation can become a serious problem. Be sure to have on proper installation, ground fault breakers and adequate power, etc. which, if distance is an issue, can become a high dollar item, but necessary for pool to function. If you are doing a cabana, outdoor kitchen, etc., in conjunction with pool - all will likely need significant (and costly) upgrades to your panel box requirements.
If it is a choice of oversizing pump(s) to accommodate the anticipated outlets and Polaris, hot tub, waterfall, etc., vs not enough pressure from undersized pumps - go bigger...
Try to avoid observation from various neighbors, etc., (which may conflict with keep vegetation at a distance,, but may influence your fencing issue) -- if you have trophy daughters and wife, they will be routinely observed without some barrier to avoid peeping.
A new pool is something to be proud of but broadcasting to a wide audience sometimes is asking for more visitors than you may be willing to accommodate.
A Polaris - or equivalent - though relatively expensive initial cost - is indispensable for helping keep the pool clean and free of most small debris.
As noted above, do not expect to get a return on your investment when you sell - and also as noted - a pool may be a hindrance to sale of your home - or not.
Salt - or not - is a flip a coin subject with proponents and opponents pro and con. If chlorine burns your eyes, skin, clothing, etc., salt is a good alternative. Either requires more time and effort and maintenance than people who have never had a pool will soon learn.