From the ATF:

https://www.atf.gov/files/regulations-rulings/rulings/atf-rulings/atf-ruling-73-13.pdf

One of the requirements under 18 U.S.C. 923(d)(1) for approval of a dealer’s license is that the
applicant has in a State premises from which he conducts business subject to a license or from
which he intends to conduct such
business within a reasonable period of time. The term
“business premises” is defined n 26 CFR 178.11 to mean: “The property on which firearms or
ammunition importing, manufacturing or dealing business is or will be conducted. A private
dwelling, no par
t of which is open to the public, shall not be recognized as coming within the
meaning of the term.” The type of business premises, as well as the business hours, is required
by 26 CFR 178.44 to be included on the application for a firearms dealer’s licen
se.
It is also provided in 18 U.S.C. 923(g) that the premises of a licensee may be entered during
business hours for the purpose of inspecting or examining records or documents required to be
kept as well as any firearms or ammunition kept or stored at su
ch premises

Hillary For Prison 2018