First, have the item at its normal daily rate.

Then, create a package. (Learn More) Creating a package for this item gives you a different price while still tracking the individual chair. You should not create a second inventory product with a different price - this will "double" the number of chairs you have.
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Next, add in the discounted rate for that item in the package's pricing.

After, in 'Contents' add the item you want to discount to this package.
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Finally, add the 'Chair Holiday Deal' to your project, and you'll get the item at a discounted rate!