Last min purchase to offset short term gains?

[Ash Patel]

I have a commercial property for sale that will likely net $70k in short term profits.  I will do my best to close on the one year + one day mark but that is four months away.  I would love any advice on reducing my tax burden.  I know how vehicles write-offs work with depreciation and leases write-offs.  What I don't know is can I purchase a vehicle for this one property between now and the sale date, then write off the entire amount when the building is sold?  I own other properties if that makes a difference.