FOR DECADES, the laws of supply and demand have weighed heavily toward landlords and the 3,000-plus real estate agents scattered across brokerage offices in Allston, Brighton, and Brookline. Historical market conditions have cemented a business model of brokers collecting a payment of one month’s rent from renters and it’s taken a global pandemic to blast a hole in the foundation of that model. Seemingly overnight, negotiating power has now been given to the renter, paving the way for innovation in the apar