Physical advertising would aim to be done mainly through A4 posters for general events with the possibility of also having bus stop style billboards for larger events. Using A4 paper for posters can be relatively cheap depending on how much the organisation is wanting to advertise events, meaning smaller events can use a smaller number of posters. Larger quantities of posters would begin to become expensive mainly through the amount of ink that could possibly be used when printing. Weather could also affect these posters if outside, so laminating or hiring space on community boards can also start to tally up in price.
For the bus stop style billboards, the content in the advertising would be the same as if it was on a poster, just on a larger scale. These will stand out much easier to the public and will often be in busier places such as the town centre. Even though normal posters can be put here too, the larger specifically designed billboards can be more in the open compared to an A4 sheet stuck to a lamppost for example. With these being securely fitted to wherever they are, it also makes them much less likely to be vandalised by being taken down or blown away by weather conditions. This could make them more effective and cheaper in the long run depending on pricing and location compared to A4 posters.
With both the A4 posters and billboards being around the same aspect ratio, the same designs can be used on each allowing easy continuity throughout different advertisements while also saving time with designing. If to be used on social media however, they would need to either be resized or have some empty space around as they use a different aspect ratio. If no changes were to be made then having some blank space would be better than cropping out elements of the advertisement, but either way the post would look much less professional and possibly lose credibility for the organisation.