She claims to be a accountant?? Where did you meet this person. Don't tell me CL. I would make sure and verify her licensing information with the state before turning her loose. If she isn't licensed properly and screws your stuff up then you will be responsible when it is all said and done with the IRS.
Word of advice. You should set up a S corp as you will pay lower taxes. As a Sole Proprietor the self employment tax rate is much higher. As a S corp you can pay your dividends from the corp earnings and not have to pay tax on them because your corp has already paid the taxes. That is how my businesses are set up. Talk with a tax expert about that.
If you have a simple business where you buy stuff for $5 and sell it for $20, you can use the bottom rung Quickbooks and the free Ebay Accounting Assistant. It saves a TON of time. It imports all of your Ebay transactions into Quickbooks.