Red flag one: input and output are blended
Welding output is the current delivered to the arc. Input current is what the machine draws from the wall. A listing that only says '200A' and '110V' without input current, circuit requirements or a duty-cycle point has not told you whether the machine can use your outlet.
The difference becomes especially important on dual-voltage machines. The 120V side may draw roughly twice the current of the 240V side to deliver comparable output. Ask for the rated input, recommended breaker and plug type for each voltage.
Red flag two: an orphan duty-cycle percentage
A claim such as '60% duty cycle' does not describe a working point. You need the amperage and voltage. A 60% rating at 100A is not comparable with 30% at 215A. The listing should also say whether the percentage follows a stated ten-minute test standard and ambient condition.
When only the highest number is emphasized, look for the manual. If the manual does not provide a clear table, the machine is harder to plan around and harder to compare honestly.
Red flag three: the accessory trap
A low price may exclude the regulator, spool gun, TIG torch, foot pedal, gas hose or even the correct power adapter. The product photo may show several variants while the selected variation is the basic box. Read every included-item line and confirm the exact configuration.
Unusual consumables can turn a cheap machine into an expensive one when tips, liners or torches become hard to source. Standard connectors and a documented parts list are useful long-term features.
Red flag four: no manual and no support path
A downloadable manual, a model-specific specification table and a visible seller or manufacturer support route are basic trust signals. A warranty badge without a covered region, exclusions, return address or claim process is less useful.
Check whether the listing seller is the manufacturer, an authorized distributor or an unknown reseller. Save the product page and order record, and ask how a warranty claim would be handled before purchasing. Price alone cannot compensate for a machine that cannot be serviced.
