You’re reading this right. Quote 2 is the classic underprepared-base scenario.
A few things stand out immediately:
“Standard base” is not a spec. It is a non-answer. In Brampton, a proper residential driveway base runs 10 to 12 inches of compacted Granular A stone, laid in 2-3 inch lifts with a plate compactor after each pass. If a contractor cannot tell you the base depth in inches and the material by name, they are not prepared to do the job properly.
No polymeric sand is a serious red flag. Regular sand washes out within a season or two. Polymeric sand locks the joints, resists ants, and keeps the field stable. On a driveway — where you have vehicle loads — this is not optional.
The math: Quote 2 at $9,800 for 480 sq ft is about $20 per square foot installed. Quality interlock work in the GTA right now runs $25 to $45 per square foot for a standard residential driveway. The gap between Quote 1 and Quote 2 is almost entirely base prep and joint material. That difference will show up as heaving and joint failure within 3 to 5 years.
Quote 1 at $14,200 ($29.58/sq ft) is a reasonable number for the scope described, assuming they actually deliver the base depth they are promising. Get that in writing — specifically the depth and material for the granular base, compaction method, and the polymeric sand brand.
Quote 3 is reasonable for Brussels premium with a decorative border.
Before signing anything, read the thread on the 12-inch rule — covers exactly what to ask any hardscape contractor before you commit.