Battery issue on customers car

no offense to any installers here, but i would never trust anyone with my car, esp. places that do 20+ cars a day (cir city/best buy ect.) i have seen some nasty nasty jobs they have done and i would be pissed if they fooked up my car. ( i know usually they know what goin on but its alot harder IMO on some older and most newer european cars)but u cant just say “if you dont trust the installer dont get it” I buy it, read all the directions, do my research and do it myself…that way i

1.) know exactly what was done
2.) know where everything is
3.) know that it was done right
and most importantly
4.) can do it again and help out friends

ok thats all