I was scared of having to figure out shipping, which is what kept me from doing this sooner.
A good sourcing calculation I do to see if something is worth my time to pick up is if I can sell if for 3x what I paid for it. For example, say I can find a Pyrex bowl for $10 that sells for $30 on eBay. I’d consider that a good investment since I’d be able to double my money after eBay and Paypal fees.
That calculation breaks down as you encounter higher-value items. I’d rather pay $100 and make $50 after fees than spend $2 and make $20. Sure, you have more money tied up in inventory that way, but I’d still rather have the extra money when the item does sell.