Self-employed prospective tenant and 1099

[Denise Case]

Screening a tenant that is self-employed. Provided a 1099 from the company he does work for which is under his company name and one month's bank statement under same company name.  They also own and rent a 4-plex so that generates some additional income after paying the mortgage.   From what I can tell they are not at exactly 3X rent but maybe close.

Credit report is not perfect (one medical bill in collections) but still in the good range.  Also, I believe their rental history is living in the 4-plex or renting from family.

Should I be asking for multiple months of bank statements or taxes?  Any advice on what else to help make a sound decision?