Regarding the scar that often results from the BCG jab, I had my vaccination done at birth before I left the hospital with my Mum. It left a tiny scar on my upper arm. Personally it doesn't bother me and it's not really visible to others unless you look very closely. However, I noticed that some of my other friends who had the jab done at birth had slightly bigger scars.
If you're worried about the scarring, you can ask for the jab to be administered in the hip or the sole of the foot. But please double check with your doctor.