When two boats share the same hull type — in this case both the Cobia Boats 21 Bay 2012 and the Cobia Boats 236 WA 2008 are modified vee designs with fiberglass construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
On paper these two are close siblings in the size department — Cobia Boats 21 Bay 2012 at 21,1 ft versus Cobia Boats 236 WA 2008 at 23,0 ft. Weight tells a clearer story for trailering families: the Cobia Boats 236 WA 2008 tips the scales at 395 lbs — 190 lbs less than the Cobia Boats 21 Bay 2012 at 205 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.
The power gap is worth calling out. Rated to 300 hp, the Cobia Boats 236 WA 2008 has a 100-hp advantage over the Cobia Boats 21 Bay 2012's 200-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Cobia Boats 236 WA 2008 carries 138 gallons versus 6 gallons in the Cobia Boats 21 Bay 2012. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.
For family outings this is probably the sharpest distinction between the two. The Cobia Boats 236 WA 2008 is rated for 7 passengers, while the Cobia Boats 21 Bay 2012 caps at 1. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Cobia Boats 236 WA 2008 could be the deciding factor.
Bottom line: Choose the Cobia Boats 236 WA 2008 if your priority is putting more people on the water — it handles 7 passengers and at 23,0 ft it has the deck room to back that rating up comfortably. The Cobia Boats 21 Bay 2012 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 1 that costs less to run day-to-day.