looking or hte best locksmith-my car's child locks are not working properly

[ipMdycguir]

i have my car BMW X1 2006 and it has child locks inside the door but i observe that from sometime that the child locks are not working properly. they randomly locks or unlocks themselves. so the locks seems useless. i want to repair t hem i have consulted with one locksmith they told me to charge over $600.00 but i found it very expensive . if anyone knows some cheaper way plzz reply me for it....