Walmart offers the Zinus 14" SmartBase Deluxe Full Mattress Foundation for $55. Opt for in-store pickup to drop it to $51.71. (Amazon charges the same.) That's the lowest price we could find by $29. It features a 13" clearance and no-tool assembly.

Also available is the Zinus 14" SmartBase Deluxe Queen Mattress Foundation for $64.99. Choose in-store pickup to drop it to $61.51. (Amazon charges the same with free shipping.) That's the lowest price we could find by $28. It has the same features as above.