Buying an engine from ebay... GOOD OR BAD?

What's up everybody.. Hope everyone enjoyed the holiday and ended it with a smile. Got a question to ask hopefully I'm in the right thread. I'm about to buy a used engine but the local shops here in my hometown are pretty pricey. What are your thoughts on purchasing from ebay? I found some pretty descent pricing engines with lower mileage on ebay than the local shops here where i live.. If anyone could point me in the right direction that be great. Really need that engine ASAP... Much love everyone