We talked humidifiers- let's chat steamers.
A personal steam inhaler, like this one for $40 on amazon, is an essential tool for the singer. The warm, gentle steam helps alleviate the sinus pressure, congestion and sore throat I get when I feel ill. This in turn helps me to avoid medications that can relieve symptoms but leave me too dry to sing healthily and with care. I also steam when my voice feels tired or the air feels excessively dry.
In addition to a nebulizer and humidifier, I consider the personal steam inhaler a necessary tool. I recommend making room in your budget for one of these!