If he wants to sell just as an individual, he can sell anything he doesn't want anymore, like clothes, shoes, books, records, cassettes, DVD's magazines etc.
However, if he wants to sell as a business seller, he would need to gain some experience first. In my opinion, he shouldn't buy a load of cheap stuff hoping to sell it on ebay and make a profit. If he lays out the money, buys a load of stuff and then it doesn't sell, what is he going to do with it?
You can't really judge what people will buy, you can only offer it for sale, and they either buy it - or they don't. There are certain items that sell well, but nothing is guaranteed.