MicrostockGroup

I'm planning to set up a photography studio business, together with a partner. Part of the business would be stock photography. I would still keep my current (personal) account on the microstock sites though.

I haven't been able to find much information about how to do that on either this forum or on the stocksites themselves, so I would be very glad to hear from anybody here who has experience with this and can give me more information, such as:

1) do all the agencies allow for companies to register, instead of people? if not, which do & which don't? Is there anything special that needs to be done for that on the specific microstock sites (SS, IS, FT, DT, 123, BS, CS)?

2) how does that mix with the requirement to upload a photo-ID (I already used my photo-ID for my personal account)?

3) how does that mix with the requirement that all uploaded pictures must be made by yourself (It's possible that they will be made by several photographers working for the studio. The rights will belong to the studio)?

4) is it possible to just let the agency take the witholding tax, or is it absolutely obligated for companies to submit tax forms to the agencies (non-US company)?

5) anything else worth mentioning like tips, personal stories, etc, are very welcome..