Attribute Pricing/Discounting: Bug, or Misunderstanding?

[hephaestus]

Okay, so I've been working through the various pricing and discounting schemes that Zen Cart supports, and I think I mostly understand how it works by now. But there's one case in the collection of demo products that comes with a fresh Zen Cart 1.3.8a install that has me seriously scratching my head:

ID# 78 - TEST 25% special 10% Sale Attribute Priced

The first two of these head-scratchers I was able to figure out myself.

On the freshly-installed system, this product was shown as follows:
--------------------------------------------------------------------------
TEST 25% special 10% Sale Attribute Priced
Starting at: $150.00(struck thru) $112.50
Save: 25% off

Please Choose:

Color [radio buttons]:
Orange ( +$37.50 )
Yellow ( +$56.25 )
Red ( +$75.00 )

Size [pulldown]:
Small ( +$37.50 )
Medium ( +$56.25 )
Large ( +$75.00 )

Gift Options [checkboxes]:
Collector's Tin ( +$37.50 )
Autographed Memorabilia Card ( +$56.25 )
Wrapping ( +$75.00 )
--------------------------------------------------------------------------

The two obvious questions about this initial configuration were:

1. Where's my 10% sale discount?
2. Why is the base price $150 (undiscounted) or $112.50 (discounted)? A small, orange thingie without any gift options should be $100 (undiscounted) or $75 (discounted).

After a little digging, I discovered that the "10% Off Sale" was initially created with an end date of 2/21/2008, and that the Gift Options weren't actually configured as "optional," i.e., they were marked as contributing to the product's base price.

After I re-enabled the "10% Off Sale," the product pricing showed up as:
--------------------------------------------------------------------------
Starting at: $150.00(struck thru) $112.50(struck thru)
Sale: $101.25
Save: 33% off
--------------------------------------------------------------------------

So far so good. But...

When I made the Gift Options truly optional (by X-ing out the violet-colored "Base Price" boxes in the Attribute Controller for that attribute), the undiscounted base price changed to $100 as expected, but the special and sale prices remained unchanged. And worse, the sale price is now higher than the base price, and the savings percentage is now negative!
--------------------------------------------------------------------------
Starting at: $100.00(struck thru) $112.50(struck thru)
Sale: $101.25
Save: -1% off
--------------------------------------------------------------------------

Huh? It sure seems like the special price should now be $75, since the special price is defined as 25% off the product price.

Although this feels like a bug, I can't imagine that I'm the first to find it. And I've looked through the list of known bugs and haven't found anything that applies. So I'm probably doing something wrong, but I can't see it.

What am I missing?

Thanks,

Michael

[Ajeh]

The Product is Priced by Attribute ...

The lowest price is the lowest price from each of the Option Name Groups:
Orange $37.50
Small $37.50
Collector Tin $37.50

This is $112.50 ...

The confusing thing is that in this example, the Gift Options are actually all optional, even though the lowest price of the Option Group Gift Options is included in the display price ...

If it was required to have this configuration using Checkboxes where they are not part of the calculations before setting up the Special, set the Checkboxes to NOT be included in the Base Price on the Attributes ...

Now work out the Special price ...

NOTE: just changing the checkboxes to not included in the Base Price without adjusting the Special Price will produce some weird results ...

[hephaestus]

The Product is Priced by Attribute ...
The confusing thing is that in this example, the Gift Options are actually all optional, even though the lowest price of the Option Group Gift Options is included in the display price ...

If it was required to have this configuration using Checkboxes where they are not part of the calculations before setting up the Special, set the Checkboxes to NOT be included in the Base Price on the Attributes ...

Well, right. That's what I did, and that's why the undiscounted base price fell to $100. But the 25% discount to the base price didn't get applied, instead staying at $112.50. So it looks like the base price calculation correctly ignores the attributes that aren't included in the base price, but they still get included in the calculation of the discounted price.

Now work out the Special price ...

NOTE: just changing the checkboxes to not included in the Base Price without adjusting the Special Price will produce some weird results ...

Ummm... what? Sorry, I'm not sure what you mean here. Could you try saying the same thing, but in a different way?

Thanks,

Michael

[Ajeh]

The Special is set based on either entering the Special Price or entering something like 25% ...

But what is really happening, is when the Special is added, the "calculated" 25% is a one time calculation ... and the physical price is put in as if you entered it manually ...

If you change the Attributes ... the Price by Attribute will change, but you still have the "old" special price and this is not recalculated to the "new" special price ...

If you were to go to the Special and enter the price as 25%, it would recalculate it ...

This is one problem with Specials that we hope to address sometime in a future release ...

[hephaestus]

The Special is set based on either entering the Special Price or entering something like 25% ...

But what is really happening, is when the Special is added, the "calculated" 25% is a one time calculation ... and the physical price is put in as if you entered it manually ...

Aha, now I see...

In fact, now that you mention it, I guess that I "knew" early on in my investigations that a special price was just a price. But somewhere along the way I managed to lose sight of it. I suspect that started happening around the time that discovered that I could, as you say, enter a percentage discount for the special price.

That, coupled with the fact that percentages seem to work the way I would expect in quantity discounts and in Salemaker, plus the fact that the sample product in question was called "Test 25% Special..." ...well, I guess I pretty much hypnotized myself into believing that they'd work that way for specials as well.

Live and learn...

If you were to go to the Special and enter the price as 25%, it would recalculate it ...

Yep, so it does. Cool.

This is one problem with Specials that we hope to address sometime in a future release ...

That would be good. It's really kind of misleading as it is right now. (At least for people like me who are easily misled! ) Until then, prominently calling it out as a gotcha in the FAQs would probably be quite helpful to successive generations of confused newbies.

Thanks for the explanation!

Michael

[Ajeh]

You are most welcome ... thanks for confirming that things worked out for you with this ...