How to solve group buying website cms

The group buying website cms has just taken over a project. it is a pseudo-group buying website. online orders are placed in the form of group purchases and funds are traded offline. The general functional modules include group buying (just place an order), bidding (four bidding modes), and membership (three levels of members ). 1. would you like to ask the experts about their experience? is there any better cms recommendation? Or a project like this is still a group-buying website cms
I just picked up a project, which is a pseudo-group buying website. online orders are placed in the form of group purchases, and funds are traded offline.
The general functional modules include group buying (just place an order), bidding (four bidding modes), and membership (three levels of members ).

1. would you like to ask the experts about their experience? is there any better cms recommendation? Or is it easy to write a set of projects like this from scratch? I have never taken over such a large project, and I am very worried about it. I have used a few cms in a simple way, but I have no idea if I start from scratch. So I asked the old birds, how can I do better with this level?

2. by the way, there is another problem. I would like to ask the experts here. this member registration needs to ensure the quality of the Member. The best way is to verify it through a mobile phone. After registration, a verification code is provided, registration is successful only after you enter the verification code sent to your mobile phone. In a word, it is a purpose to ensure that every member is real, rather than being written in disorder. This is the best from the customer's perspective. However, this SMS Gateway Interface has never been used, and some materials have been found until the end of the page. the official stuff is missing. I don't know if you have done anything similar. You can also use other methods to ensure that the membership information is authentic.

3. there are also a lot of miscellaneous functions, such as the calculator, how much I spent on this item, and then a variety of taxes can be combined to get the final price.

4. call electronic maps, etc... If it is electronic map, is Google better or Baidu better? I also need to mark many things on the map.

These are my concerns. I hope you can help me with your experience. The main problems are problems 1 and 2. 1. Are there any cms suitable for my website? If not, change it or write it by yourself. 2. how to perform this verification to ensure the authenticity of members.

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Secondary development with Ecshop should be able to meet your requirements. Of course, it can be completely re-developed. Your questions are not very serious. you can go to the official website to check whether anyone has done them.