Eighteen months would span two growing seasons. That's quite awhile to be without a mower. It's day you have five options.

1. Don't mow your lawn. Not a good option as it becomes very unsightly.
2. Hire a lawn service.
3. For a lot less than two seasons of a lawn service you can buy a pretty nice used lawn tractor. A couple years ago my big lawn tractor was in for service and it was taking awhile to get parts. My grass kept growing. I picked up a pretty nice rider on Craigslist for less than $500 to use on 3 acres. I kept it for the rest of the season even after I got my big mower back. I sold it the following spring for $20 more than I paid for it.
4. This is how they did it for many years before lawn mowers were invented. $75 or so and it's good exercise.

5. I don't know where you live but this could be an option.

Compratene uno usato.

Offrirlo ai nuovi acquirenti di casa. Se non lo vogliono, puoi provare a venderlo al We're outahere garage sale, on-line, per esempio tramite Craig's List, o un servizio di vendita di proprietà come Everything But the House. Se tutto il resto fallisce, se può essere donabile ad un no profit per il loro uso o per la rivendita.