These are evidence leads, not recommendations. The advertised services are not equivalent.

Discovery lead What its own website documents What to establish before deposit
TIE MEN — Hanoi and Ho Chi Minh City Describes paper patterns drafted for individual clients and successive on-body fittings. (tiemen.vn) Who drafts and updates your pattern; which intermediate fittings your itinerary includes.
SIR Tailor Lists suit starting prices of VND 7.9 million with Asian cloth and VND 16.9 million with Italian cloth, with full canvas described as standard. (sirtailor.com) Exact cloth reference, applicable service tier, final price and overseas correction costs.
Nathan Tailors — Hoi An/remote Advertises a US$149 starting price for a wool-blend two-piece and guided self-measurement for remote orders. (nathantailors.com) How fit is assessed before completion, who owns measurement errors, and what is included beyond the garment.
WAS Concept — Ho Chi Minh City/Singapore Advertises measurement in Ho Chi Minh City with collection in Singapore, plus Singapore consultations and fittings. (wasconcepttailor.com) Whether the proposed route includes substantive intermediate fitting—not merely collection. This page does not establish US fitting support.

Do not convert this table into a price league. The entries differ in cloth, construction claims, fitting route and remedies. VND figures are left unconverted rather than implying a fixed dollar quotation.