Well, currently in the us if you file from i-129 here with uscis, it will take about six months to get a decision from them. You do have the option of expediting it by paying a fee of $1,200 or so and they'll give you an answer within 15 days or give you your money back. But most people go through the embassy in their home country. And usually the processing time Is two to four weeks to get a decision. Embassies are strange in that they vary. They're all under the umbrella of the state department and you would think everything is very standardized. But different embassies have different practices. So there's no blanket thing that can be said about the processing time.
The important thing is you recognize the lead time involved in submitting your visa. And by that i mean your business plan has to be prepared and you have to have already actively made investments in your business. And those are the things that take time, not the processing.