The average 3x4 feet poster can cost around $80-100 + tax. Options are usually matte/satin or glossy.
a) Before you send a poster to the printers, it is recommended that you convert your file to PDF.
Consult this checklist first.
b) Need to convert your files to the right colour settings? Use a program like Adobe Photoshop or Adobe Acrobat Pro to convert your poster colours, so that the original colours remain true.
Pro tip: Print out and assemble a large full-size draft using plain paper sheets (8.5 x 11), to see if there are any alignment, colour, font, or image quality issues. This also makes it easier to sport tapas spot typos.