Know any good geotechnical engineers in the Columbia, SC area?

[Qais Attarwala]

Hi, I have a duplex (one side crawl space and the other is on raised slab based on what the seller told me) that has stair step cracks on the exterior wall of the slab unit, drywall cracks in both units, and bad supports under the crawl space unit side. Should I get a geotechnical engineer to come out and do an analysis to tell me if there is settlement vs soil heave or something else? I figured I should do this so I can get an accurate scope of work to bid out to contractors and I have already tried reaching out to several engineering companies but they all said that they deal with commercial properties, not residential. Know any reputable and fair engineering firms that can help me with residential foundation evaluation?