The tidyform website offers a template for a basic rental agreement that covers only two sides, so it can be printed on a single page. Reducing the form more than this is difficult without using references to external documents.
Since a rental agreement needs to cover the rights and responsibilities of both the tenant and the landlord, it is difficult to reduce the length of the document to much below two pages of text without using references to external documents clarifying those rights and responsibilities. The 'Lectric Law Library does offer a very short form template, but this provides space for additional terms to be added, and any additional information is likely to bring make the form more than one page in length.
Basic information that must be included covers the rental term, possibilities for extension, notice periods and the rent payable. Any terms specific to the rental such as permission for the tenant to keep pets, restrictions on noise and alterations, and rights and duties regarding maintenance on both sides should also be included. It is useful from the landlord's perspective to include information on termination rights and methods of seeking redress, as well. Information on whether the lease can be assigned or transferred to another person is also valuable.