I would focus on maintenance starting out. Profit margins are less typically than landscaping, atleast for me, but maintenance is my week in and week out cash flow that is always there. With landscaping, when your done with the job your basically unemployed until the next one comes in.
Many people have said put some back for cash flow and maintenance. I agree totally with this. Your will save yourself a lot of stress having a cushion.
Get clients that you can service with equipment you have. This is much better than buying equipment for work you dont have.
I agree a good back pack blower is a must.
I wouldnt buy the dump trailer, it seems like its to much of your available cash. Youd be better off spending that money on advertising and you'll be able to afford a better trailer and other things off the work you get.