Full Answer
Visible cost (monthly subscription) is the tip of the iceberg. GTM solutions require: initial developer setup (50-120 hours), ongoing maintenance when things break, updates when Facebook/Google change APIs, infrastructure scaling as traffic grows, and emergency fixes when tracking fails on peak sales days. Client-side only has different hidden costs: 30-40% data loss means algorithms train wrong, ROAS suffers, and you waste 5-15% of ad spend on misattribution.
