The accounting and tax distinctions that actually change which lease type makes sense.
A $1 buyout lease is structurally a financed purchase — you're guaranteed ownership at the end for a nominal $1, and payments are priced accordingly (higher than a true lease). An FMV lease gives you the option to return the equipment, renew, or buy it at its fair market value at term end — payments are lower because the leasing company retains the residual-value risk, and the equipment may not stay on your balance sheet as an owned asset.
Under the current lease accounting standard (ASC 842), most equipment leases — including ones previously kept off-balance-sheet as "operating leases" — now must be recorded as a right-of-use asset and a corresponding liability on the balance sheet. This changed how leasing affects reported financial ratios; talk to your accountant about how a specific lease will actually show up on your books before assuming it stays off-balance-sheet.
The Section 179 deduction can let a business deduct the full cost of qualifying equipment in the year it's placed in service, rather than depreciating it over several years — and depending on how the lease is structured, a $1-buyout-style lease may qualify while a true FMV lease generally doesn't, since 179 requires the business to effectively own the asset. The dollar limits and qualifying rules change periodically, so confirm current-year figures with a CPA rather than relying on a prior year's numbers.