I'll throw a couple things out.
Get great, not good, with a chainsaw, it's one thing doing it on the ground and something completely different! Believe me! You really have to think ahead on how this is going to affect that, "slow and low" as it was told to me.
People suck! I got a call to bring the mini out for a small stump removal, hubby had had a heart attack and wife figured he was going to die getting it out. I told her $45hr 2hr min, cheap right? I show up, pop the stump out and load up. She starts both Bing I was only there 20min! "I shouldn't have to pay that, that's just not right!" After another 20min of this shit I told her I had to load everything, drive across town, do the job, drive across town, and unload everything again! Hubby finally jumped in, "Just pay the man, it's what we agreed on!"
They have no concept what this equipment costs or how expensive it is to maintain it! Two months ago I dropped $450 to put tires on my trailer, last week was $250 to redo the deck on my trailer, it goes on. Chains, tires, filing time, clean up, dump time, bid time, driving here and there.
For a weekend warrior I'd look at clean up and home owner drops. Quick and dirty work you can get in and out of. Show up, slice a little, throw it on the trailer and out in a couple hours. Drop the gnarly tree for the HO and let him clean up the mess type work. You can't afford to get tied to a job that runs long because it was bigger than you thought. That wears you out, leaves a pissed customer waiting until next weekend, kills your rep and screws you for the next weekend. Remember, things do go wrong!
You are also going to have a bigger fight with weather being a weekend warrior, you've got a two day window, full time crews have seven days.
Also, this is a big one for me at least, bid the job for you! Meaning you are part time, sometimes you'll have help, sometimes you won't! I had a smallish concrete job once, buddy swore he'd help. I told him when and where, he showed up two hours later, right as I was pulling the forms off the steps. It was only 10yds, but some flatwork, steps and it all had to be wheelbarrowed in! I was flag I'd figured that job alone, if it had been much bigger I was screwed!
Just some food for thought.