Hi Chirag,
I guess your question is already answered above. I am not sure about Kalina's process, but from what I have read, it does take time. Attestation at Churchgate is quick. Go through this link of basic instructions for application at Churchgate. The process is very smooth.
http://mu.ac.in/portal/wp-content/uploads/2014/03/Procedure-for-Attestation.pdf
Make sure you visit there at before 11 am and collect your application form, which also has your queue number.
You will need - bonafide/transcript from college (they told me its mandatory, but didn't even check), 2 sets of each of your documents to be attested, Originals for verification, 2 envelopes for each set, WES address handwritten on both the envelopes,
Charges - Rs. 5 per document and Re. 1 for each document in the second set.
Hope this helps.