A landlord, from time to time, may adopt rules or regulations, however described, concerning the tenant's use and occupancy of the premises. It is enforceable as provided in section 76-1431 against the tenant only if:

(1) Its purpose is to promote the appearance, convenience, safety, or welfare of the tenants in the premises, preserve the landlord's property from abusive use, or make a fair distribution of services and facilities held out for the tenants generally;

(2) It is reasonably related to the purpose for which it is adopted;

(3) It applies to all tenants in the premises in a fair manner;

(4) It is sufficiently explicit in its prohibition, direction, or limitation of the tenant's conduct to fairly inform him of what he must or must not do to comply;

(5) It is not for the purpose of evading the obligations of the landlord; and

(6) The tenant has notice of it at the time he enters into the rental agreement.

A rule or regulation adopted after the tenant enters into the rental agreement is enforceable against the tenant if reasonable notice of its adoption is given to the tenant and it does not work a substantial modification of his bargain.