You need to learn a lot more about the blisters. The mere presence of blisters tends to severely rate down a survey and hence resale value, but they may or may not be a problem. Cosmetic blisters through the gel coat but not deep in the laminate probably should be repaired over time, but they have little effect on the boat. Structural blisters, large in size and deep in the laminate require early attention. A boat with cosmetic blisters can be a great buy.