i started my biz last year at 18 yrs old mainly focused on maintenance. all i had was my f150, pushmower, weedeater and handheld blower. all equipment borrowed from dad. tried flyers but only yielded like...3 biweekly clients. started using craigslist and got a wealth of biweeklys and 2 weeklys. end of the year i ended up with around 50 accounts. i have 3 commercial mowers(exmark pushmower,toro walkbehind, and toro grandstand) all sitting in my brand new 2013 enclosed trailer. I only used craigslist! And yes, i am licensed.
Give craigslist a try if your looking to build your maintenance up a bit. No, you wont get the higher end clients, but you gotta start somewhere. Eventually you'll look into new ways to advertise to the specific market your trying to service.
As for landscaping... im not the guy to ask about getting that kind of work. And i know you have a full time job and cant put alot of time into maintenance because of that, but if you need to make some cash, you gotta take what the Lord will give you.
Best of luck to you!