Re: Im a little CONCERNED about this quote for a 14x28 Vinyl...
Let me address some more of your questions, many pool contractors buy pool equipment in bulk from which ever of the major brands they can get the best deal on, then charge a premium for any changes. This makes sense from a business point of view, by have the same brand and family of pumps, filters, etc. (in a few sizes to fit most pools) there is less hassle in installation, simply repeat how you did it on the last job. On the topic of ionizers do a search on this board about them, I personally think traditional chlorine or SWG is a far better way to go. I should mention here that there is a certain environmental movement that wants everyone to think chlorine is evil, while I think they do have some points, I do also think they are greatly oversimplifying the issue and demonizing Chlorine even in cases like back yard pools where most of their base points are moot. On the topic of sand vs cartridge vs DE filtration, I had used sand filters for many years before switching to DE a couple of years ago, the choice can be a very personal one, however sand is still the common defacto choice for many contractors. Sand is seen as cheap, simple and good enough, much like the car rental industry only offering cars with automatic transmissions, everyone can drive one, not everyone wants the headaches that come with the extra performance of manual transmissions (ie. DE filter).
To sum things up, the list of equipment the contractor lists seems fairly sound except ionizer, Hayward super pump is a good solid pump that does not cost a fortune, no brand listed for a sand filter, so may be generic, but then again sand filters have not changed much in the last 40 years. Plumbing seems a bit excessive, but there seems to be a trend going that way, and it is a cheap way for the contractor to up sell, better than the too common minimal plumbing that has been common in the past. Hayward 500 watt pool light is about as standard as you can get, although you should be aware there is a big move towards LED lighting going on now. I don't know what your goals are, location looks like, etc. If your looking at cutting upfront expenses do away with the ionizer and get on the BBB method of using bleach for chlorination, you might also want to skip on the heater for now. Have it built (plumbed and wired) to add one later, this will shorten your swimming season a good bit, but I assume you ar still several weeks away from breaking ground, and would likely only get a little use out of the pool this season. Also as has already been noted hold off on pouring the deck, let the ground settle around the pool first, sure it will be ugly at fist, but then you can build the larger deck area you want later.
Ike