Question: How can I find a comprehensive directory of all out-of-home advertising inventory in the US?

If you're looking for a single source to catalog all out-of-home (OOH) advertising inventory in the US, OneScreen.ai is a great option. It maintains a publicly available directory of OOH inventory, including all types and vendors in the country. The company also offers more advanced planning data and analytics to help marketers plan and execute their OOH efforts. On top of that, it offers tools for strategic media planning, media buying and campaign tracking.

Another option is MediaRadar, an advertising intelligence platform that offers profiles and contact information on brands and agencies. It also includes directories of advertising reviews and product categories that can be useful for media planning and targeted sales pitches. MediaRadar is geared for media buying, sales and planning, and can help you keep up with market trends and new business opportunities.

If you prefer a data-first approach, InMarket is a platform that helps brands reach customers with real-time marketing and measurement. It offers solutions for scaled audience reach, AI-activated marketing, attribution and actionable analytics. The company's Real-Time Optimization technology can help improve campaign performance, so it's a good option if you're looking to optimize media performance and get the most out of your advertising budget.

Last, Choozle is a digital advertising platform that offers a range of media inventory, including digital out-of-home (DOOH). It offers advanced targeting options, real-time reporting and AI-optimized campaign performance. It's geared for agencies and brands trying to get the most out of their advertising budget across multiple channels, so it's a good option for those looking to plan and buy media across a wide range of channels.