It's not clear to me what is happening with the mortgages. If your client is paying off the old mortgage, then taking out a new morgage for the acquired property, I think the basis calculation is straigtforward. 

The basis of the acquired property is reduced by the deferred gain. And, its basis is increased by the exchange expenses.  

For your problem (assuming mortgages are paid off, not transferred)

Old property 

Purchase price = $69,000

Depreciation = $14,000

Adj Basis = $55,000

Gain = $212,500 - $55,000 = $157,500

Realized Gain = $157,500 - $15,926 = $141,574

New Property = $357,500

Basis Adjustment = $141,574

New Property Basis = $215,926

Any suspended losses transfer to new property