Information is Key
It is easy to become paranoid these days, what with all the readily available technology out there, that some one might in fact be monitoring us. While the suspicions you have might be true, for the average person it is more likely a pre-existing source that is providing the means to intrude rather than it being applied external devices.
Many companies will offer bug sweep or removal services but often do not comply with true industry standards and you are essentially placing your peace of mind and safety in to reckless hands. If you are truly in a vulnerable position and in need of true technical surveillance counter measures make sure you find a resource that is an expert in the field. Please contact us if you would like more precise information regarding your needs.
For the average person vulnerability audits often are enough to discontinue potential privacy invasion. An audit is specific to your case and will include what is required to ensure your property, electronics and person are secure.
What we mean by a pre-existing source is usually an internal surreptitious source that someone has access or a means of monitoring. Auditing your cars, home and electronic devices are effective means of securing any vulnerabilities you might be aware are being exploited or used against you. This will include a broad range of assessment from your phone to your house hold trash.