Start a lawnmower without a key?

Is it possible? I have a yard machine lawnmower, I have to jump start it, with jumper cables every time I use it. Now I lost the key! My mistake was buying another yard machine brand. It cost $1,300. It only ran for one hour. The store says it is my problem. I told the company I would tell everyone I could not to but Yard Machines! Anyways, back to my actual question, Is it possible to start the old lawnmower, without a key??? My gr is getting REALLY long! Thanks.