I found this PDF form online at the Ohio BMV
It is the Form that affirms you have a Non commercial Vehicle. looks like you print it fill out get notarized and bring to the your local BMV office.
Notice the box you check
" REGISTRATION AS MOTOR HOME
 A self-propelled vehicle used for the sole purpose of recreational travel that has no fifth wheel; is constructed with
permanently installed facilities for cold storage, cooking and consuming of food and for sleep; is not used for the purpose
of engaging in business for profit
, in intrastate commerce, or for the purpose of commerce as defined in the federal
commercial driver license law; is not regulated by the Public Utilities Commission under Revised Code chapter governing
certain motor carriers"