We will install almost all equipment you purchased online. You can use this link to setup an appointment https://mobilemaxaudio.com/schedule-an-appointment/
Just be warned that even though you are having the equipment professionally installed unless you bought it from an authorized online seller the manufacturer will not honor the warranty.
For example if you bought an amplifier off amazon and it stops working after being installed due to a factory defect or improper use the manufacturer of the amp will not replace it.
While it’s uncommon for new electronics to fail it does happen and you will be left with the bill or the replacement and re-installation.