Hey buddy, I started lawn care / landscaping this year after I started leaf cleanup last year.
Leaf cleanup was awesome ! I made 9k in 6 weeks, that was really great.
The years before the leaf clean-up I had mowed 3-4 properties for the year on a weekly and bi-weekly basis.
12 years before I started my lawn care business I had done snowplowing, average snowplowing income is generally 13-26k depending on the snowfall.
For snowplowing I have retained all my own customers except 2 for the past 12 years.
( the 2 I lost were losers, I lowballed to get the job then bumped the price up 5$ more per push and he decided to go with someone else LOL, The lot was dirty, looked like crap and he didn't even have a back blade for the commercial lot haha ) If he calls this plow season ima bump the price up another 15 where it should have been lol @ 30 bucks a push, sure it only takes 10 mins but I am a good plow guy imo... the other guy took about 30 mins per push when he plowed.
You should start your business this year, don't worry about LLC or S corperation unless you owe money or have a personal lawsuit against you that may put a lein on your business accnt with your ss# or sole prop tax id.
Go for it ! You need not worry about things that may not happen, what you need to worry about is the steps it takes to make it happen and stick to it.
I now make an average of 3k a month just cutting lawns part time.. I cut lawns Mondays Wednesdays & Thursdays weather permitting.