Not familiar with the TroyBilt but any commercial 36 would most likely be a huge upgrade. I bought a used JD 36 for $500!! Deals are out there and it fires up first pull anytime I need. Just remeber to buy a mower for your current lawns, not what you plan to get. That can be a big ol waste of money. You do some really nice work at only 15, you got a long ways to go in the landscaping world. Keep it up.