Should you hold the property or should you sell and lease it back??

You bought the property 6 years ago for $1,000,000. Today it could be sold for $5,000,000. If you hold it for another 9 years, it can be sold then for $9,000,000.

The "building component" of this property is 74%, and it has a 26-year depreciable life.

You face a 37% tax rate on all taxable income.

If you choose to hold the property, rather than selling and leasing it back, how much money would you need to pay in total taxes at the time when you will be selling it?