Chicago's Tenant Opportunity to Purchase (TOP) program, effective March 1, 2025, allows tenants in certain neighborhoods to have the first chance to buy their rental buildings when landlords intend to sell. This pilot program aims to combat gentrification and preserve affordable housing until 2029. Landlords must notify tenants 60 days before a sale, and tenants have varying time frames to act based on the number of units. Non-compliance by landlords can result in daily fines, and tenants can seek legal action for enforcement.