We are a team of web designers and developers with 800+ sites to our credit. We have developed and integrated custom CMS (in PHP and MySql) for many of these sites.
I have seen the reference site. It is fairly extensive. I always prefer working against detailed specifications - that helps deliver as required. Trying to clone sites may result in missing out on many backend features. I request for detailed specifications (complete flow, functionalities, fields) that will help me to assess scope of work. I will revise my bid based on this.
I ensure a good job and look forward to hearing from you.