I have 2 jobs that I need some advice on how to charge for. 1st job is a 150' x 100' lot that needs to be mowed. 2nd is a commercial property that has to be cleared & cleaned up for new construction-apartment complex. Will be maintaining complex once its built. The lot I will charge by how long it takes to do it- $50-$65 depending on trash if any. The clearing & cleaning for new constr. is where I'm not so sure... Any suggestions?