Houston does not rank as one place. Google reads Katy, Sugar Land, Pasadena and The Woodlands as different searches with different competitors, and a single Houston page cannot answer all of them.
The metro also has plenty of masterplanned neighborhoods with their own names, from Cinco Ranch to Shadow Creek Ranch, and people search by those names. Older housing near Pasadena and inside the Loop has different problems from newer builds in Fort Bend County.
Zillow, HAR.com and Realtor.com own most listing searches, so local firms win on service and area terms. The Google Business Profile matters as much as the website, since many local calls start from the map.
Search patterns follow heat and storms through the year. TREC covers brokers, Texas and city rules cover trades, and HeyLead is the marketing team, not the license holder.