There is a glut of office space in Oil Town, and one potential landlord is offering 3 initial months free to new tenants who sign a 3-year lease. Oilfield Engineering's current offices are slated for demolition, and their potential new lease is for $4000 per month. If their interest rate is 1% per month, what is the equivalent monthly cost for a 3-year lease? What is a comparable monthly lease cost?