What should a RFP include?

I was contacted for a RFP with very little information, but it is from a legitimate business. I have done proposals for many clients before but normally I have a lot of information or an initial meeting with the client before writing up the proposal.

The proposal is just asking for a direct Mail campaign, something I have a ton of experience in, but direct Mail can vary a lot by so many factors.

Should I try to setup a meeting or just ask for more information via email?

I've read on here that RFP are not worth the time or effort but want to work on this type of documentation for my business anyways. I think I was contacted because I am a WBE. Any input is appreciated!