For me 2 examples of products we already use are simple green and baking soda.
Baking soda I have used for deodorizing and for pet stains . The baking soda absorbs the odors in the carpets and allows me to salvage some of them. It also combined with water and scrubber it has been a handy tool in removing hard grease stains found in units.
Another example is simple green. there many uses for this product but the one we've found is to clean our boiler system. It cuts out the grim, dirt, black soot, it really does an amazing job.