Asterisk, PBXinaFlash (like Trixbox), A2Billing VOIP System configuration

We have a PBXinaFlash system running on a CentOS 5.0 LAMP. DIDs, trunks and A2billing etc are working. The tender winner can have full remote access and control of the system via static IP or domain name using FreePBX or Webmin [telnet etc can be arranged]and I can access the server directly if needed. We require decent documentation for all work done so that we can build an identical system by myself on our backup system. The project is divided into essential and optional components. Please QUOTE ON ESSENTIAL COMPONENTS ONLY and then tell me which of the optional components you are able to do (with costings) in your comments. 1. Customer ESSENTIAL (i) A php website template that allows customers to sign up, login to check balances and make payments through A2Billing linked to a PayPal business account. (ii) The template does not need to be a work of art but should allow me to use Dreamweaver to insert my logo / promotion and have all relevant input boxes, dropdown menus and other components working. (iii)Customers should be able to pay in their choice of currency [Yen, Yuan, Won or Baht]. (iv)Three separate services are available and the customer should be able to click on a button and have the template insert the correct charge in their local currency. (v) Customer must enter their country and native language. These fields need to be added to their billing details in the A2billing DB [and/or any other relevent DBs or scripts so that these fields can be implemented in a dial plan if needed] 1. Customer OPTIONAL (a) SMS message sent to customer [in addition to email] when they sign up or make a payment (b) Recorded voice message sent to customer's telephone [in addition to email] when they sign up or make a payment. (c) Customer can make payments by phone after web sign up [it's OK if they first have to enter payment details once off on the website]. (d) Call Back Button on website to start call back service [as outlined in section 2] so the customer does not need to pay for a telephone call to get the service. 2. PBXinaFlash / A2Billing / Dial plan ESSENTIAL (i) Customer dials into system from their city's DID or via the website Call Back button [if available] (ii) System checks the customers account number and PIN or recognises their telephone number and authenticates them if a match is found. (iii) System connects to an available agent (iv) System calls back the customer on their telephone number. (v) Client is billed a FLAT FEE after enough time to ensure the callback is made and the agent is connnected to the customer. (vi) System disconnects the callback at a predetermined time 1 minute after a voice message warning of the time limit. (vii) System provides enough information to enable agents to be paid for each callback. (viii) Customers receive voice messages / prompts in their native language. 2. PBXinaFlash / A2Billing / Dial plan OPTIONAL (a) The customer is informed if no agents are available after dialling in to the system and asked if they are willing to accept a callback latter. If willing they are then prompted for the latest time they will accept the callback. If an agent becomes available before this time they are called back. 3E. Agents ESSENTIAL (i) Agents need to be able to log on when available from REMOTE extensions [ie their home telephone numbers or mobile phones] or via a website and log off from either interface when not available. The system should register the agents as available or not and then disconnect. Available Agents remote extentions should then be called if there is a callback for their ring group. (ii) The system needs to reflect the agents availability in real time [or very close to real time]. (iii) Agents to be grouped in ring groups of three or four agents based on longest log on time without a call. (iv) Up to 5 ring groups [formed in real time on the criteria in (iii)] should be present in the dial plan if enough agents are available. Dial plan should call the longest waiting ring group first followed by the second longest waiting group etc. (v)A php website template that allows agents to log on or off [same standard as Customer website] (vi) Agents should be dealt with as not available when taking a call. 3. Agents OPTIONAL (a) A php website template that allows agents to sign up for work so that their details can be easily imported into the system if hired [same standard as Customer website] Please feel free to suggest any additions etc. that will make both our jobs easier in your comments. Just refer to the options by their number and letter e.g. 3(a) for the last option. Payment in full within 3 days after successful completion to allow time for testing. We realise this is our first use of getafreelancer so we don't have a rating yet as such we MAY be willing to to make a part payment after a stage completion. Please let us know in your bid if you will require this. Also be assured I have been around software design and system development for quite a while, you can expect reasonably intelligent responses to any queries and a fair degree of flexibility in approach provided the outcomes are met and the code is clean. Thanks Grant