I would suggest a process flow like:
1. Internal Purchase Request (IPR) - Creation and Approval
2. Request for Quotes (RFQ) process
3. Comparatives of the Quotes including approval flow for the Comparative
4. Conversion of the IPR to a Purchase Order (PO)
5. Multi-level approval of the PO based on Order Amount
I would suggest a process flow like:
1. Internal Purchase Request (IPR) - Creation and Approval
2. Request for Quotes (RFQ) process
3. Comparatives of the Quotes including approval flow for the Comparative
4. Conversion of the IPR to a Purchase Order (PO)
5. Multi-level approval of the PO based on Order Amount