The documentation you should have with you during your interview is your employment contract, business card, and recent proof of income, such as pay stubs or bank statements. You should also provide detail of the expected cost of the trip and whether your startup is paying for the cost of the trip. The consular officer will want to see that you know what activities are permitted under a B-1 business visitor visa, such as attending an accelerator program or educational, professional, or business conferences; consulting with business associates; finding office space; or negotiating contracts.