As a sole proprietorship, you do not have to have worker's compensation for yourself. You can even apply for and obtain an employer identification number as a sole proprietorship giving you the ability to hire one or more assistants. However, as soon as you hire someone, you WILL have to comply with all of the federal and NY regulations arising from the employer-employee relationship. This does mean having to pay workers comp insurance for the employee(s).
Some folks will try characterizing their workers as independent contractors, which means they don't bear responsibility for withholding wages and providing benefits and workers comp insurance. The amounts paid are reported on 1099 forms.
In your case, treating your assistant(s) as independent contractors would be a bad idea on several levels. First, your situation does not look like a classic independent contractor situation. Second, you live in NY, where the employment laws are likely to be assiduously enforced.
First, I generally think it is a bad idea to run a business as a sole proprietorship. It makes you more suspect to audit by the IRS and that is the last thing a growing business needs. Dont ask why statistically speaking that is the case, it just is.
Second, I agree with my colleague, you run a risk by trying to pass off an assistant as an independent contractor. They probably will not be classified as such based on the IRS standards.
As a sole proprietorship, I think one of the biggest overlooked concerns is establishing the proper distinction between person and business i.e. establishing proper business accounts, proper record keeping, service contracts, terms and conditions of service, website disclaimers etc. These things are more important than you may think.
Contact a business attorney.
Look, in NY you would be insane to even think about hiring anybody without first consulting a lawyer in private that can evaluate everything. For example, NYC just passed the Earned Sick Time Act (ESTA), which requires employers to pay for a certain number of sick days. The laws keep changing and I have little doubt that what you described would be an employee/employer relationship. And beyond this issues you have other legal considerations, entity structure, trademark, service/sales agreements, etc.
I suggest that you consult with a lawyer in private and discuss your objectives in more detail. You can start by calling around to several for a free phone consultation, get some insights then pick the best fit to work with.
DISCLAIMER: this is not intended to be specific legal advice and should not be relied upon as such. No attorney-client relationship is formed with the law firm of Natoli-Lapin, LLC on the basis of this posting.