Get insurance before you set foot on a job
As already said, get a 48 or 52 walk behind (belt drive will save you a ton) and a 21 mower for small stuff. I would get the best back pack blower right off the bat cause you need it.
Get a attachment type trimmer so you can edge and trim with one machine.
The whole referral thing has never worked for me.
Fully plan on working another job or working part time to get it going.
What are you going to be towing/trailering with?