The system you require is straight forward, I suggest for issues of long term maintenance that it be built utilizing the Excel DDE from the API, if its coded in any other framework the issue of forward maintenance and internal modifications and upgraded by your firm will be complicated and costly.
Yahoo, and other such as Google Finance, will ban the connection if their systems are accessed too frequently by an IP address, which effects the issue of the "real time" data. Once the IP address is banned it is hard to re-establish the service.
I have built similar systems from scratch using Excel as the Web server and DB.
Developing the basic functionality of the system is not the challenge, the challenge will by synchronizing the report interface you want, the reports are a qualitative issue and not a quantitative issue.
I can complete the initial build in 10 working days, the stress testing and revisions will have to be coordinated between us and should take another 10 business day.
I specialize in Financial Engineering and have created similar applications for similar trading systems for several years now.
If you have more requirements please let me know.
Cheers,
Gerald Staruiala,
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