Asterisk PBX - advice and some customisation required.

I am currently working on a proof of concept and trying to get some buy-in on an internal project... The project is small, but if successful, I hope this leads to an opportunity for continued collaboration. I am looking for some help to speed up completion of the proof of concept. I am using Asterisk 1.8 and all seems to be working well enough but would like to add in a few standard Asterisk features (I've done this in the past with a build of Asterisk 1.6 on CentOS 5.5 using FreePBX - however, I want the set up to be WITHOUT using FreePBX) Requirements: I have 4 SIP peers/extensions set up already, and I can make internal calls between them using a softphone. I also have a SIP trunk in place. My requirements are as follows: - Accepting a call, be able to blind transfer the call to another extension (I can actually do this already) - Restrict which numbers can call certain internal numbers based on caller ID (the caller could be internal or external) - Play a message if a somebody calls or tries to transfer to an extension that is not allowed - giving the user the chance to try another extension. - Implement Follow Me on an extension, so it is possible to simultaneously ring two numbers (Internal extension, external landline or external mobile) or call the numbers in a particular order - Ensure that only certain extensions can make outbound calls though the SIP trunk and to the numbers specified within a Follow Me - Set up IVR on each extension so that when the recipient at the extension receives a call, they have to enter a number on their keypad (soft phone or hard phone) to accept the incoming call. This will apply on internal extensions or external numbers (i.e. if the follow me has routed through to an external landline or cell phone). Providing the code and instructions in Office format would be fine (that allows me to implement in the Asterisk development/proof of concept environment I have in place) and maybe be available for a small amount of follow up support if any questions.