Bromley is London's largest borough by area, with a business base that cannot be reduced to a single trade. That is a very different setting from a page aimed only at homeowners looking for a contractor.
Bromley Town Centre is the borough's Metropolitan Centre and its largest concentration of shops and offices. The Glades is part of that picture, but so are the independents, practices and smaller businesses working in and around the centre. A retailer seeking visits, an accountant seeking appointments and an SME selling across South East London should not be given the same campaign or the same definition of success.
Real Google Keyword Planner research shows local searches for both “PPC agency Bromley” and “Google Ads agency Bromley”. Bromley was one of the few areas where both 'Google Ads agency' and 'PPC agency' searches registered in Google's 10 to 100 a month band. That is evidence of local agency interest, not a promise that every campaign will find hundreds of buyers. The opportunity still depends on what your customers search for and how well you serve them.