You mentioned starting an online business which begs the question as to whether you plan to organize an entity (such as an S corporation, a C corporation or a multi-member LLC).
Be advised that there TurboTax Live (Full Service or otherwise) does not support preparation of income tax returns for the entities listed above; the service is only for individual income tax return preparation.
Further, you might find that you need the individual (CPA) in the firm to assist you with aspects of your business (and commercial property) beyond income tax preparation. For example, collection and payment of sales tax, maintaining books and records, etc.
