I think that's a bit over critical. I don't offer a free manual J on a bid, nor do I provide the AHRI, but I do provide the SEER of the equipment. The way I see it, they can either meet or beat the SEER rating with the match-up. It's up to the dealer which model will work best for the application and based on the conversation with the homeowner. The basic model is given but not the full number, i.e. Trane XR17, but not 4TWR7048B1000A. Going into those type of details is a waste of time, because the customer will typically have no idea what you're talking about, and it leads them to shop price not dealer installation quality.
That's not to say dealer is free from providing properly sized and rated equipment.
SEER rating is a sales tool by the mfg. Don't get too hung up on those numbers. They are created in test laboratory conditions with non-typical air flows, lineset lengths, etc. Find a dealer that you can trust to help deal with your home comfort concerns. When a customer starts shopping AHRI and model #'s you're basically shopping the lowest price.
Your dealer should ask questions, and provide means to deliver on remedying your concerns. If you find a dealer pushing numbers, walk away he/she's a "salesman".
To answer your question, SEER is based on the ratio of cooling capacity vs. energy consumption over the course of a whole cooling season. If you average your electric bill during the cooling months and compare that to your lowest bill when you're not using heating or cooling, you can derive a cost of cooling per season.
The next seer rating typically 16, is ~ 12.5% better than 14 SEER. So, if you spent 100/mo for 5 months to cool your home that's $500/season. That's a whopping savings of $62.50 per year! Wohoo! It would take ~16 years to recoup your investment.
