An IRS notice should be read carefully before deciding whether the response is simple or whether professional representation is warranted.
First identify the issue
Some notices are computational or informational. Others involve unreported income, examinations, penalties, collections, or disputed tax positions. The type of notice determines the level of expertise required.
Representation rights matter
If the matter may require advocacy before the IRS, ask whether the professional has appropriate representation rights and whether the person regularly handles the type of matter involved.
Do not assume the original preparer is the only option
The person who prepared the return may be the logical first call, but a separate representation specialist may be appropriate for a complex examination, appeal, or collection issue.
Respond deliberately and on time
Do not ignore the notice, and do not send an improvised explanation simply to meet a deadline. Understand what the IRS is asking for and what documentation supports your position.
Authoritative reference: IRS — Understanding your IRS notice or letter