Here is what I did years ago to build my cleaning business prior to going into manufacturing.
Every job we did, we left door hangers on as many neighboring homes that we could. It could have been only 2 hangers or 20 depending on time constraints. If there was time, we would walk down the street and put hangers on the entire block. The cost of the actual hangers, was neglidgeable yet the return on the investment was well worth the time spent doing so.
On other occasions when doing commercial work, we would also walk around and provide free no obligation quotes for the cleaning of neighboring businesses especially in malls.
Getting your name and number out there is the key to your success.
If there was down time, we would do the same and blanket neighborhoods with "special" fliers to entice people to call. We would also hit all of the apartment complexes within a certain radius and provide competitive quotes. Just because the actual cleaning is only worth lets say $45.00 there are always areas to make more money such as urine inspections, Kool aid removal and repairs/stretching to raise the job tickets.
We also offered special incentives for referrals, Meaning if a current customer referred us to another person they would receive a special incentive. It could be anything from free protectant to a room or 2 cleaned for free. You would have to decide what works for you by trial end error.
I built that busniess from a single truck to three within 2 years. Just remember that "failure is not an option".
Good luck and I hope this helps..
Jim