Yeah, paper thickness, paper finish (glossy, etc), colors, format, recto-verso, ... it all counts in price. So be carefull with comparing prices and always ask what is included or not.
You can also use the backside of the flyer to have the 'small print' on it, or put some long legal text or whatever (costs of course also more). The front should be like just a few catch phreases...
Putting a nice picture on it of yourself (and your team?) washing a car always works too (as long as it is a nice professional looking photo of course), it makes it more personal and people can then put a face on the business. This is always a good thing... (unless you look like a hobo
)
Oh, and actually be carefull with 'glossy' paper. It often is too shiny to read something on, especially in well lit areas. It might be better if you choose semi-glossy or just non-glossy. (I forgot the name of the type we always use on our flyers and booklets, it is not glossy, but also isn't plain normal but something in between; it doesn't reflect but still looks extremely well and colors still come alive).
PS: that speedo meter picture seems to be licensed as "attribution work" (you must give credits) and "non-commercial use only" ... so be carefull as you business is obviously commercial...
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