Although there is time spent creating these contracts and acquiring signatures, it is up to the freelancer wether to sue a client for non-payment. When considering the expense and time commitment for following up with legal proceedings, it could be a bad investment if it is for a small dollar amount. That means obtaining signatures is somewhat ceremonial. However, a signed document is always taken far more seriously than an unsigned one between the parties involved. If you have client that is not paying on time, these strategies will often work:
Instructions for creating a digital signature using Adobe Acrobat Pro
Note: Be wary of non-disclosure and non-compete clauses in agreements. Reference the 'Special Contract Language' in the 'Employment Types' section for information regarding these.
Note: The invoice, as is the case below, is often identical to the estimate. That is good business because the client will be expecting them to match.
Sample Estimate click image to enlarge
Sample Invoice click image to enlarge