When I was 15, I Started with a Craftsman LT3000 Rider with a 42" mower deck, a ryobi trimmer, a small backback blower, and a 4.5ft*8ft trailer. Worked with it for 2 months and realized it wasnt right. so i sold the tractor, trimmer, and blower and bought a
-John Deere GS45 54" Commercial Walk Behind
I got really got prices on the machines and i borrowed some money from my parents but I was always cutting grass so it paid for itself quickly.
As for the trailer, I used the same one for my first season but because its just 1.5in big enough for my mower, I knew i had to get a bigger one. So i found a 16 ft double axle landscaping trailer that i also had to borrow money again but i had made enough last season to have most of it paid off.