In an effort to serve the most users given a limited number of hours for data entry, for guaranteed inclusion in the database a car, SUV, or minivan must be purchased by more than 1,500 people in the average month. The tally currently includes over 170 2006 models and over 130 2007 models. The main categories affected by the volume criterion are high-end luxury cars and sports cars. I also have not yet entered any pick-up trucks because they each involve about as much work as a dozen cars and I'm not sure how many people would be interested. However, if enough people email me requesting an omitted model, I'll enter it.
What's in the price comparison database?
Modes: User, Min, Max
I created this site because I personally wanted a quick and easy way to compare car prices. Not simply base price to base price, but with a specified level of equipment. To facilitate this process, I have created three modes. In the first, "User," you check off the specific features you want, and the TrueDelta algorithm then figures out which packages and feature combinations best supply these. With the second, "Min," every feature standard on one car and available on the other is selected. With the third, "Max," every feature available on both cars is selected.
What are standard values?
Standard values are fixed values assigned to features. They are the same for every model.
This permits TrueDelta to provide some guidance on feature cost in the feature selection list and to calculate feature-based price adjustments.
The standard values are based on the low end of what manufacturers charge for these features. Where no option prices are available--generally for minor features--I've estimated. The resulting adjustments tend to bring trim lines within a couple hundred dollars of one another, so they're not far off the mark.
Values are only provided for features that can be readily compared. I don't venture values for engines, tires, seats (except $300 for a third row), or audio systems.
How are the price adjustments calculated?
It's rarely possible to equip two models exactly alike. To provide a more precise price comparison, the Adjustments Table tallies up the standard values of features that aren't shared by all of the models and trims being compared. These values are provided in parentheses next to the feature description. It then subtracts the smallest total from the others, and finally subtracts the resulting figures from the corresponding prices. The adjustment to invoice prices is the MSRP adjustment multiplied by the ratio between invoice and MSRP.
Can I get unadjusted price differences?
Yes -- just look at the "Net Price" and "Net Invoice" figures in the Price and Invoice tables. If you want prices without rebates, then look at the "Total Price" and "Total Invoice" figures in the same tables.
Standard, Option, Package, Not Incl.
The Adjustments table notes which unshared features have been included in the price for each trim line.
Standard: standard equipment
Option: a standalone option (though it might have prerequisites)
Package: part of an option package or included with a "purchased" optional feature
Not Incl.: not included on the trim line as priced; for possible reasons (beyond unavailability) see below
Where'd that feature go?
In all three modes illegal combinations are dealt with by striking the less valuable requested feature from the list.
In the "User" mode a table of eliminated features is provided.
There is one very important difference between these three modes. In "User," the algorithm will do whatever it takes to get all of the requested features. If a $10,000 package must be purchased to obtain a $20 feature, it'll do it. In contrast, the other two modes will only "buy" a feature if not too many unrequested features must be purchased with it. It'll "buy" roughly $400 of stuff to get a $200 feature. Past that the feature is removed from the request list for both models.
Where'd that feature come from?
Because manufacturers often group options into packages and require one option in order to get another, you'll notice unrequested features in the results tables. Sometimes many unrequested features. Especially in "User" mode.
Why didn't an available feature show up?
Your selection of powertrains, tires, and other "complex features" determines which trim lines will be included in the process, and thus which features will be available. Only rarely will the TrueDelta algorithm alter a powertrain selection. If you know a feature is available, but it is not being listed, try a different powertrain. If in doubt, don't select tires and audio systems. The model page, accessed by clicking on the model's name on the complex features page, shows which complex features are available on which trim lines.