I think this is approximately the same thing. In UK, this is a pre-contractual document, i.e. it outlines the terms under which a lease will be signed, so that the parties can agree these, but it is not the contract itself, so the parties can still decide not to go ahead.

ある事務所の翻訳ですが、不動産業でどのように表現されているかは不確定
参考までに：

This is just my idea. "manual" for 説明書 seems to be pretty standard, although it always depends on what kind of 説明書 it is. In U.S. English, we tend to use "issues" rather than "matters", but this also varies depending on the context. I read that 重要 can take on the meaning of "urgent" which would sound more natural here, but I hate to add meaning to a translation unless I can confirm the nuance with the client. So, my suggestion is very basic. Good luck!