Answer:
$174000.
Step-by-step explanation:
Given: Property value= $220000.
Site value now = $50000
Estimate depreciation= $4000.
Using cost approach to find the estimated cost of improvement.
The cost approach is method to estimated the value of property by adding value of land and depreciated value of improvement.
Formula; Cost of improvement=

⇒ Cost of improvement=

∴ Cost of improvement= $174000.