You can get the Constitution Train Chase (79111) for $54 at Yoyo.com with the use of coupon codes. The set is on sale for $89.99 but if you apply both coupon codes NEXM4193 and 20LABORDAY at checkout, it will discount the set even further by another 40%. With coupons the total discount on this set will be 46% off.
The codes can be used on any item at Yoyo.com if you’re not interested in the train set.
For those that don’t know, Yoyo.com is owned by Amazon. If you’re in a state that Amazon doesn’t charge tax in, Yoyo.com will also not charge tax.
Edit: The coupons no longer stack. You can only use one code at a time now.