When two boats share the same hull type — in this case both the Weldcraft Marine 173 2011 and the Weldcraft Marine 188 2009 are deep vee designs with aluminum 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 — Weldcraft Marine 173 2011 at 17,3 ft versus Weldcraft Marine 188 2009 at 18,7 ft. Weight tells a clearer story for trailering families: the Weldcraft Marine 173 2011 tips the scales at 1 305 lbs — 1 169 lbs more than the Weldcraft Marine 188 2009 at 136 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 150 hp, the Weldcraft Marine 188 2009 has a 35-hp advantage over the Weldcraft Marine 173 2011's 115-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Both carry nearly identical fuel loads — 42 gal and 42 gal — so range won't be a tiebreaker here.
Both boats are rated for 5 passengers — a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.
Bottom line: Performance buyers should lean toward the Weldcraft Marine 188 2009 and its 150-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the Weldcraft Marine 173 2011 with its 115-hp rating is the more economical daily driver.