Asterisk Dev for Custom PBX System

I'm seeking a proficient Asterisk developer who can build a custom PBX system with Issabela or something comparable. The PBX system requirements are as follows: - Less than 10 extensions. - Features such as call recording, auto-attendant, and call routing. - Compatible with VoIP phone lines. Ideal candidate should possess a deep expertise in Asterisk and a good understanding of VoIP technology. Knowledge of Issabela or similar software is an added advantage. Let's connect if you can guarantee a seamless and efficient communication system. For more information, sent the requerimients - The calls received would be answered by several receptionists who would log in/unlog in with their landline to receive the call. If there are more calls than receptionists, a message will appear indicating that they will assist you immediately. - The receptionists would route the calls to the agents available at that moment, who in turn would log in/unlog in with their landline to answer the calls. - For receptionists there would be a real-time panel of incoming and active calls, as well as receptionists and advisors logged in, free and busy on calls. The receptionist could select a free agent and forward the call from the panel or do it through the physical keypad of her phone (for example # 250) - For each customer call, the receptionists would receive a card showing their name, telephone number, comments, purchases made (date, time, amount, minutes, payment method), calls made, and available balance of minutes. - The customer balance system would consist of minutes that would be automatically deducted when speaking with agents (not receptionists). The client's balance would be indicated by a voiceover at the beginning of the call. The way to buy balance would be through the IVR gateway, during the call through the receptionists, or through a php script to which the OK data from the banking web gateway would be sent. - Among the minimum necessary options there would be a panel for editing/information on clients, agents, receptionists, call and payment history, as well as reports on minutes per agent, reports on last purchases, minutes per client, etc. - Receptionists, agents and clients could have Spanish or international numbers of up to 20 digits. - The system would have the option of blacklisting phones that would block the call. - There would be the option to upload and add voiceovers at different points, times and cases - Calls can be charged per minute or without a charge per minute. Different types of calling services can be established with their corresponding configurations/locutions/IVR, they would be called services. - There would be administrator and receptionist roles, each with different options. The receptionists, each one would have their extension and independent login on the panel, to be able to receive and transfer different calls at the same time. Call example: - Customer calls a service phone with a per-minute charge. If you do not have a balance, the purchase announcement skips (Press 1 for a 12-minute bonus, 20-minute bonus, etc.). If you have a balance (or if you buy it at the locution), it is routed to the landline of the first free receptionist (if they are busy, we will assist you right away). Panel: Receptionist sees that there is a call listening to the purchase announcement, or if she has a balance she sees that there is a call coming in. She also sees call/s queued to be received on hold if there are any. - Logged in receptionist answers the call on your landline. Panel: The receptionist sees the client's information sheet, name, phone number, comments, purchase history, balance, etc., modifiable. The purchase option also appears in case the customer wishes to purchase more balance. Here the receptionist sees the list of busy and free agents, and selects a free agent to transfer the call she is answering. - Receptionist has already transferred the call. Panel: the receptionist can see in real time the busy agents (and the name of the client they are with) and free agents, the time on call, number of calls answered, average, and disconnected agents (which could be connected/disconnected manually) . - Another example would be the customer service number that would be another service with no charge per minute, in which clients would enter (with/without balance) to make queries, reservations, complaints, purchases with a receptionist where she would modify their file to add the bonus manually, etc. Summary and general concepts Customer Person calling the switchboard. It has an associated balance of minutes, among others. Agent Person who assists the customer and whose conversation with the customer entails a discount on the balance of minutes. Receptionist User who takes the call in the first instance and transfers the call to a free agent. She can also modify balances and other data associated with the client. Requirements: a) Customer management The system is required to manage the following information associated with calling telephone numbers: • Name (editable) • Phone # (editable) • Comments: an editable text field. (editable) • History of purchases made • Calls made • Balance of minutes available to speak with agents (editable) This information will appear to the receptionist on the control panel when she picks up a call from the phone number. b) Automatic call cut-off When a customer ends up speaking with an agent (not a receptionist) the fee must be deducted