An E1 visa is not as concerned with the investment as it is with the trading. An E2, however, would normally require around $100,000. You would not change the visa if inside the U.S., but rather, your status. You would have to contact the attorney to determine costs. The proof and documentation for a successful E1 or E2 is extensive and you should contact the attorney directly.
Brian D. Lerner
Attorney at Law