Deciding between a full-size ski boat and a small outboard motor might seem like comparing apples to oranges, but for anyone shopping the boats personal watercraft space, the real question is how you'll spend your time on the water. Do you want a complete boat that can pull skiers across a lake, or do you need a portable motor that will push a dinghy or a small fishing boat? These two products sit at opposite ends of the spectrum, and both have a place in a boater's life.
Quick Verdict
If you're ready for an established ski boat, the 21' 1990 Supra Mariah is the clear pick. It comes as a complete package with a trailer and the kind of care a well-kept boat usually shows. If you just want a dependable, easy-to-carry motor for a tender or a compact fishing skiff, the 3.5HP outboard wins on simplicity and portability. The budget difference is enormous, but the two solve very different problems.
Price and Spec Comparison
| Feature | 21' 1990 Supra Mariah | 3.5HP 2-Stroke Outboard |
|---|---|---|
| Price | USD $8,000.00 | USD $177.75 |
| Condition | Used | New |
| Engine | Inboard, gas | 2-stroke gas, manual start |
| Fuel | 11-20 gallon capacity | 35:1 fuel-to-oil mix |
| Size | 21-foot hull, composite | 35.4 x 15 x 7 in, 28.66 lb |
| Best For | Fresh-water skiing | Dinghies and small fishing boats |
Where Each Product Wins
The Supra Mariah wins for anyone who wants a full-size tow boat with room for a group to enjoy a day on the lake. Its composite hull and engine are well matched to ski-boat use. The outboard wins when the mission is portability. It's light enough to lift and includes the tools and mixing bottle you'll need for that first run. If you already own a dinghy or a small boat, this is the least complicated way to give it power.
Product Notes
21' 1990 Supra Mariah Boat
The Supra Mariah is a one-owner boat that has been stored indoors, and the details show it: all stainless hardware, a new gel coat, and a new rubber rail. The upholstery and carpet are in good condition, and the 351 PCM Cleveland block has 785 hours on it. A dealer inspection and new tires on the Trail Master trailer mean it's ready to be hitched up and moved to the water. Choose it if you want a complete, inboard-powered tow boat for fresh-water skiing rather than a project. The limitation is the package itself: it's a boat from 1990, so you're taking on an older engine and the storage and maintenance any full-size rig demands.
3.5HP 2-Stroke Gas Outboard Motor
This little motor turns a dinghy into a practical runabout. It's a 3.5hp (2.5kW) 2-stroke with a CDI ignition system, manual pull-start, and a 35:1 fuel-to-oil ratio. It moves a small boat at about 12 km/h with four people on board, and it comes with a water pump impeller, a starter, a funnel, a mixing bottle, an English manual, and all assembly tools. For a compact fishing boat or a tender, that package is genuinely turnkey. The limitation is power and reach: this is a small, portable helper, not a motor that will pull skiers or push a full-size hull, and you'll need to mix oil with your gasoline every time you fill up.
Final Choice by Use Case
If your next season involves slalom runs or tubing behind a ski boat, the Supra Mariah is the one that can do that job. It's a substantial purchase and a substantial boat, but it's also a complete package with a trailer and the kind of older-boat character that many ski enthusiasts really want. If you're piecing together a lightweight setup or just need to turn a little tin boat into a runabout, the 3.5HP outboard is the obvious call. It won't give you a tow-sport platform, but it'll get you out to fishing spots and back for a fraction of the investment.
