According to the Arbitron study, billboard advertising is effective. Billboard advertising is effective for building brand awareness and broadcasting your business (or product or campaign) to as many people as possible. Because they're in such busy areas, billboards tend to have the highest number of views and impressions when compared to other marketing methods.

 Additionally, 56 percent of people reported later talking about a funny billboard they saw while on the road. A smaller percentage tuned into a TV or radio show because of a billboard ad or noted a phone number or web address displayed on one.

The cost of billboard advertising depends on many factors including the location of your billboard, the total traffic in the area, and how many people are estimated to see your advertisement. Billboard advertising costs are typically charged monthly.

My idea is to replace this advertisement notice type of board with digital billboards. Also, there are many advantages and disadvantages over there : 

Advantages : 

1) Digital billboards provide even greater creative freedom.

2) Saves humans repetitive work like replacing the posters.

3) Easily manageable through the Internet

4) We can automate this thing via servers which can automatically replace the default poster after contact completion

5) The client can also see the validity and situation of there contact through our website and can change there poster by just uploading a new image.

6) We can manage clients using servers and send them reminders for new contact and current status.

Disadvantages : 

1) Initial installation cost will be high

2) Need Maintenance of this system