It is impossible to answer your questions with such limited information. NO ONE can tell you.
The cost of the insurance will depend on MANY factors.
1. What type of business is it?
2. What is the potential exposure?
3. Any employees? If so, how many?
4. How dangerous is the work, service or whatever you will provide?
I am a small business owner and deal with insurance companies all the time. My policy is renewed every year and with different underwriters you get different questions. There are many, many more questions that need to be asked and answered before you will even get a ballpark answer.
ETA: Market conditions also have a LOT to do with setting insurance premiums. Depending on the type of business, location and market conditions your premiums will vary from year to year even.
I have paid anywhere from $70,000 to $110,000 a year for the same type and kind of business even with the same amout of volume and employees.
Your best bet is to contact an independant insurance company and sit down with an agent and have them prepare a quote based on all the info. they will need from you.