HOA Special Assessment for Roofs and Staircasess

Our condo association levied a special assessment of $525 per year for four years beginning in 2019. The money will be used to replace roofs and staircases on each building. The roof replacement on my building was completed in 2019 but the staircase won’t be done until 2022. Since the total cost of the improvement is less than $2,500, can it just be deducted as an expense each year instead of a depreciated improvement? If I have to add it as an improvement, do I add the total of $2,100 to the cost basis in 2019 or only the amount I paid in 2019?