Hello Sir,
I have gone through your project requirement which requires to create a barcode Id functionality for the customer and have to write a module for the payment method .
Sir I would like to mention that I will do it for you in quick time and can start right now.
Further, I am a Magento Expert (Client Speaks,can see the review) having more than 4 years of experience in eCommerce ,providing solutions as per their requirements.
I have build more than 40 eCommerce stores based on the Magento.
I have build many custom modules including custom shipping methods,payment methods,pickup modules,daily deals and many others.
Apart from development I have also very good understanding in performance enhancement.
I have worked on Varnish, Memcache, Apache Solr.
I am sure I will meet your requirement and provide you good solution.
Looking forward to hear from you.
Regards,
Ankur