Chris and Christa arguing with Joel and Sheila how to properly pronounce "realtor" is a meta joke based on criticism of the word's pronunciation during the first season.
Sheila (Drew Barrymore) says "Finally, a worthy adversary." Tim Curry says these exact words in Charlie's Angels (2000), which stars Barrymore.
Skyler Gisondo and Maggie Lawson both starred on Psych together (Gisondo as young Shawn and Lawson as Juliet).
At 10:13 -Hollywood cliché #018: without computers and cellphones there is no way to further the plot.