South China’s hottest new advertising opportunity is … toilets.

Restrooms in Guangzhou should soon be full of business opportunities, according to a plan for a new project proposed during a local government conference.

The city should encourage in-restroom businesses that would contribute to budget for restroom improvements, the plan suggested. Potential businesses would include commercial advertisements in the bathrooms as well as toilet-paper vending machines.

Beijing has pushed a nationwide “toilet revolution” ever since President Xi initiated the campaign to modernize restrooms in 2015. However, the campaign policies offer toilet projects in urban areas little in the way of confirmed long-term material support – and so the pressure is on cities like Guangzhou, where most toilets are free, to shore up funds for toilet maintenance.

In 2018, Guangzhou’s municipal government spent around 250 million yuan ($37.28 million) on the construction and renovation of 1,027 toilets. That means the maintenance fee could surpass 150,000 yuan per city toilet, according to Caixin’s research. As the city hopes to both build and maintain even more restrooms this year, the financial burden of commodes has become a major challenge.

Guangzhou is not the first city to invent new methods of financing the toilet campaign. Xi'an, home of China’s famous terra cotta warriors, subsidizes toilet maintenance. And Suqian, a city in Jiangsu province, has already approved commercial plans similar to Guangzhou's.

Related: No Room to Rest in China’s ‘Toilet Revolution’