Purpose is to give advice on purchasing a used cassette walkman based on the many I have purchased online via Ebay.
Units made in Japan and Malaysia under reputable brands such as Akai and Sony are best value for money. A lways get one with tape selection ie metal/cr02 as the audio range is higher. Auto reverse units are preferable as they save battery life on rewinds.
Units fitted with AVLS are great as they limit the sound output so you don't get any nasty noises from eratic sound recording changes. Mega bass function is also preferable as it gives depth to the sound which cannot be normally added due to lack of tone controls in these units.
End of the day the cosmetic appearance usually reflects the condition of the internals so bid wisely and make sure detailed photos showing all sides are viewed before bidding.