I have POA for my Aunt. Can I use her money to pay for an Elder Attorney for advice?

All services, fees, supplies, etc. that go toward the care of your Aunt should come from her assets. You should not feel odd about using her funds to get advice about her care. You are a caring niece.
I set up an online account with my Mom's bank. That way I can keep track of her accounts, pay bills, and access other banking info.
If there are "nosy" relatives that may inquire about the use of her funds, just keep receipts and make notes in her bank register.