Dear Diana,
Not all "Biochars" are created equal. Thorough characterization of the material must be done to assess its value and usefulness. The inclusion of tires and biosolids, for many buyers, will detract from the value. If the "landfill wood" is not sorted to eliminate painted or treated wood, the material may have no economic value.
At the current time, I recommend two people for serious characterization of charred materials:
If you already have your material characterized, then we should talk.
Hope this helps.
John