I just had it done from a silencer shop near my office (I-10/3 Automarket). the guy was quiet reasonable and quick with it, took me only 30-35 mins. although if you want you can get it from any decent silencer shop just tell him to wash it properly and dont damage the "mitti" :).
service charges vary between 1000-1500 but please make sure they take the bumper and front patti out if you have a non-CVT model, hardly takes 10 mins for the whole removal and assembling but the mechanic has to be insan ka bacha. if they try to push the CAT out any other way they may damage something, also the oxygen sensor grip is very tight but the good thing is that the whole grip slides out towards the left so you dont have to break the clip. also disconnect the battery terminal before the procedure else there is a small screw at the back of alternator which carries +Ve charge it has a small rubber cover on it but still can touch and spark with the CAT if forced that way.
for ABS, just reset the ecu and hopefully it will go away, if not than check if the grips for both front sensors are still connected, turn steering left and look behind the right wheel (driver side) where the break disk cover is located there is a small sensor with wire going inside the engine bay. just check if that is connected, or if there is metal deposit on the sensor itself (u have to take wheel off to see the sensor head).
