Most of the houses we work on across our service area went up in the 1980s and 90s, with a median build year of 1986. Libertyville skews older than that - its median build year is 1976, a full decade earlier. That gap matters more than it sounds like it should. A door and opener installed in the mid-70s to early 80s is a different animal than one from a 1990s build: different spring wind counts, different track widths, sometimes a jamb-mounted opener bracket instead of the header-mounted setup that became standard later. When a Libertyville homeowner calls about a door that groans on the way up or won't respond to the wall button, the fault often traces back to hardware that predates the parts most trucks carry as standard stock. We bring both generations of parts because this area needs it more than most of the towns we cover from Gurnee, 6 miles up the road.