Help with sink install
If your wall pipe is 1 1/2&quot; and you're installing 1 1/2&quot;, you'll want some kind of non-glue coupling (seriously, don't glue that tail piece on). There's one in the drain section for slip-joint coupling, but if you don't care about aesthetics ( I have mine in a cabinet so it's not a big deal to me, but I can't tell if this would be exposed or not), I prefer the rubber couplers from the PVC line aisle (they hold the pipe better). The catch there is that the rubber couplers are sized for inside diameter, while your thinner PVC drain parts are sized for outside diameter (they're so thin the ID and OD are practically the same). So you would buy a 1 1/2&quot; coupler in the white PVC next to your drain stuff, but you would (confusingly) buy a 1 1/4&quot; coupler in rubber because the OD is 1 1/2&quot;.
Skip the CPVC adapters, primer and glue. I would also skip the compression fittings and just buy a push connector (i.e. Sharkbite). I found them to be about $1-2 more than their compression counterparts, and for one sink you'll save more than that skipping all that CPVC stuff you'd waste. Plus there's no hassle. Just cut, push and you're done (you might only need the water off for 5 mins tops like this). And the push connectors are likely to be the superior quarter-turn ball valves, which are far easier to operate.