If it's a sound runner and the battery is usable, definitely. The most common risk with a second hand low cost lithium e-bike is a dud battery that cuts out as soon as it hits a load such as any climb. These cheaper lithium batteries typically have an up to 2 year life, often shorter but almost never longer. In any event, a replacement battery will typically cost over £300 and they are priced up to around £500 for the best ones.
If you can't try it first it would be a very risky buy, privately offered warranties can be worthless.
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