The thing with advertising is...
different things work in different areas and in different markets.
Something that works in one area will completely fail in another area or market.
I was in advertising for over 20 years and companies would experiment with leaflets, brochures, bus advertising, posters, point of sale, direct mail, magazine and newspapers, radio... the list goes on. The key word is experiment!
Read through the posts and most have had bad experiences with Facebook. Some have had brilliant responses. They are both right. Obviously you have to get the message right or you will fail in all areas.
Just try different things and see what works for you.
I have had good responses (good ROI) from leaflets, google adwords, google business plus, referrals, sign writing, I’ve never lost money in any area of advertising. But some work better than others. Experiment to find the best way of advertising that works for you and hit it.
For instance...you could set up a small stand in tesco’s foyer and canvass every customer that comes out!
I think they still let you do it!