If you do not have an image in an text editable format as PSD with layers or other vector format, it is not easy. We need to hide the original informations with the retouch tools (Clone Stamp, Healing brush and so on) and write the text again. Because the file formats you have (PNG, JPG) have no layers, the text in your original file is not editable. It will require more working time than just professional typographic change. Therefore, I assume that the price you mean is the price for one image.
I have different complex experience in:
Layout design, image design, typgraphy design and preparation for printing.
I have over 30 years as a print designer and media designer for various printing, design and advertising projects for large and medium-sized publishing and advertising companies worked.
I have practical knowledge in the Adobe Creative Cloud work programs (InDesign, Photoshop, Illustrator) and the other recognizing design-technical trends.
I have many practical experience in print design, media design (printing) and preparation and control of the printing process, including high-level work.
For further questions and information I steal at any time.
I thank you in advance.
Yours sincerely
Michael Michelson