Price automation for ecommerce online platform

I need a customized program to fetch data, calculate and update offer price of an online ecommerce platform (2 sites - basically the same with different marketplaces). The program shall be split into 2 parts - one part to fetch the data from ecommerce platform, calculate the offer price, output the result in an excel file and upload to Google drive (email automation too). Another part shall log in the platform, take the calculated price and update price in backend. The program shall be able to run 7x24 in a VPS environment. Developer shall suggest a reliable and low cost VPS provider. Output excel file for each fetching shall be uploaded to Google Drive. Only the latest file shall be stored in Google Drive - that is old file shall be cleared from Google Drive. The output file shall also be sent to corresponding Google email account. The ecommerce platform does not have any API. Developer shall be able to handle platform robot detection, captcha, proxy blocking etc. If proxy service is required, developer shall advise such service provider and monthly cost, in addition to handle the work. Good database design and management are necessary. Developer shall provide 3 months warranty to ensure the program can run 7x24 in VPS server. Document and all necessary information shall be provided to ensure buyer can have 3rd party to do maintenance work (both the script and VPS set up details). Buyer will pay for VPS and proxy service every month. Developer shall include the cost for proxy service required during development and testing. Applicant is expected to send a sample data fetching file (say 20 items from ecommerce platform), suggestion for proxy service and VPS server providers (as well as suggested monthly cost for such service). Total project time shall include 7 days testing (7x24) showing the program is working properly. Payment schedule 1st milestone payment - 80% of project cost, when the project testing (7x24 without problem) is completed, submission of code and complete documentation for VPS / proxy service set up & control. Document shall (with screenshot) show how to maintain the program in VPS (e.g. re-start the program etc.). If there is any error, 7 days period shall be recounted. 2nd milestone payment - 20% after 3 months warranty Only serious and professional shall contact me for detail requirement file. Only seller can accept the above payment conditions shall apply. All auto response to the project will not be considered.