Google Ads Lead Generation Management

I run a nationwide business and already have a Google Search campaign in place, but the cost-per-lead is creeping up while conversion volume is flattening. I need fresh eyes on the account and ongoing optimisation that reliably drives more sales enquiries from a national audience... (Budget: min $50 AUD, Jobs: Digital Marketing, Google Ads, Google Adwords, Internet Marketing, Lead Generation, Looker Studio, Marketing, SEO)