Co-applicants - commercial (retail) lease - who should sign?

[Michael W.]

A woman wants to lease a retail unit in a building I manage. She will be running the business exclusively. However, She said that she's building up her credit and that only her husband will be signing the lease. I ran a background check on the husband, which was satisfactory. Should I require her to undergo a background check and to sign the lease as well? My feeling that everyone who has an ownership interest in the business must sign the lease. Thoughts?