This Honda 21" 3-In-1 Self-Propelled Lawn Mower drops from $429 to $399 to $389 with code HDSPRINGBF through 4/13 at HomeDepot.com. Plus, delivery is free right now! With free shipping, this is the lowest price we found and it goes for up to $489 elsewhere (update: it's here for $350 via code 179771, but shipping is $105). It's also one of Home Depot's best-reviewed lawn mowers , with 248 reviewers rating it 5 out of 5 stars. Sales tax is charged in most states.