Good chance that finding out the condition is the single most-vital thing anyone will want to know.
This amplifier was built as a hot rod. High performance, but easy to drive into a ditch, so to speak. Checking a car for a bent frame is not tough, but identifying damage in a big amplifier like this one can be more subtle. Damaged parts that are shorted out internally may look perfectly okay.
This one probably has type "8930" tubes. This one has become rather expensive the last ten years. Could be that the three tubes have a higher market value than the whole amplifier in working condition. There are more people looking for tubes right now than there are people looking for this amplifier.
But this is a bit like buying a car parked in the front yard with weeds grown up around it. They may tell you "Just needs a battery, drive it anywhere".
If you can't demonstrate that it works, you can expect only offers around the salvage-value price. It has a few additional parts inside that are expensive. Expensive, as in roughly the price that the working amplifier might bring. Not so different from a 4-cylinder front-wheel drive four-door that needs a motor.
Could be that this amplifier is "totaled", because it needs parts that cost more than it would in working shape.
Could be that it's in perfect condition. But if you can't convince the buyer, he'll only want to pay salvage price.
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