The April 30 deadline for homebuyer tax credits of up to $8,000 pulled many sales forward, likely draining activity from the usually heated spring and summer months. Economists say it will take several more months before its clear whether the market can stand on its own or retreats anew after the credit’s demise. New and existing home sales likely were robust in April as buyers raced to beat the deadline for the credit. This would follow a five-month high in pending sales of previously owned homes in March.