One of the most common non-tax questions clients ask tax professionals is “How long should I keep this?” “This” could mean bank records, copies of tax returns, or virtually any other piece of business information. This reasonably comprehensive overview focuses on keeping business records for tax compliance, specifically, what to keep and how long to keep it in case a taxing authority ever decides to examine (audit) a business return. Records management is an entire field unto itself! Hiring an in-house records manager is beyond the needs or the budget of most small businesses, but it’s important to understand that proper records management is serious business.

How Should a Disregarded Single Member LLC File a W-9?
Although Form W-9 has some other purposes, a company will usually ask you to fill it out if you are a business-to-business service provider . If you don’t provide a TIN to your customer, they may have to subject you to backup withholding . If it is my company that asks you for the W-9, I am not going to do backup withholding if you don’t send me the W-9. I’m just not going to pay you until you cough it up.
I believe in learning from experience. But it is better if the experience you learn from is other people’s experience. That is why a very large percentage of my tax writing is from court opinions, most often the United States Tax Court. This piece is my own experience.