Most new business' fail because of having to much debt.
You then need to realize that most LCO's started out without spending any where near the money you are going to. And you are not spending wisely.
You bought a closed 7 x10 trailer.
Open trailer is less money, if you read here most people recommend a 6/7x12 trailer. That extra 2' length makes a big difference. And open saves money.
Then you put a down payment on a trailer? Either you buy it or you don't. What is stopping you from pulling the trigger, money, no truck?
Right now you have more free hours during the week then you have work.
This means you can make do with a pickup, and two wood ramps, and your 21" mower. Then get a that br 600, line trimmer, a stick edger, sthil hs45 hedge trimmer.
Now you have all that money behind you to expand smartly.
Come the spring you may want to get that 7x12 open trailer to haul debri's doing spring clean ups. And you will be ready for when you add larger mowers.
Then once you hit your 10th customer you add a 36" WB to increase your capacity and you will get through most gates so you won't have to do the back yards with the 21" mower. And you should be able to get that mower into the pickup bed.
Once you paid off the 36"WB and get yourself up to 15 accounts you look to get that 48" to a 60" mower to increase your productivity. You then keep the 36" for the tight spots and small gates.
Then you set aside the cash to buy equipment. Equipment that is paid off can never be repossessed. Debt free is the only way to weather the economic down turns. There will always be good times and bad times to come.