What is the cost and how successful is a pulsed dye laser for treating post-acne red marks?

Pulse dye laser treatments will vary depending on the provider and your geographic location.  In general, this is a good laser for a variety of lesions (including scars) with a vascular or red component, though several treatments may be required depending on the appearance of your skin and its response to treatment.  See your dermatologist or plastic surgeon for a consultation, as you may need to consider a combination of laser types to see maximal aesthetic benefit. 

Costing will depend on your provider, however treatment success can vary. The most consistent results will have some transient and mild swelling and bruising. My suggestion is to have this done over the weekend. Often for post acne redness, especially lasting over a decade, higher settings are needed and you may require a series of 3-4 treatments spaced 3-4 weeks apart for optimal outcomes. Dr Davin LimLaser and aesthetic dermatologistBRISBANE, Australia