A.S. Babu Sah
This shop is decades old and the real deal when it comes to Kanjeevaram saris. With over three floors of saris including silk and cotton, they keep a wide variety of collections. The quality is trustworthy, and the rates are fixed. The range for silk starts at INR 3,000 and may run into lakhs for a single sari.
It's better to have a budget in mind and convey the same to the salesperson as soon as you enter the store. They don't allow photography, but you can do WhatsApp video call to get selection help from family or friends. The INR 20,000+ range of silks here is perhaps the best selection of designs and colours you may find anywhere else in Kancheepuram.
Pro-Tip: Don't get confused by other fake stores with similar sounding surnames.