Canon 6D flash recommendations, cheap for student

[nataliefaye04]

Hi!
I’m looking for possible recommendations of flash that I could attach to my Canon 6D. I am only a high school student so I would like (possibly cheap) recommendations of any brand, I always use my camera at the beach and on trips but I take disposable cameras to partys and I’d like a flash so I can use my camera instead I don’t plan on taking portraits or ever being in a study sadly ahah. 
I’ll buy the flash off eBay (that’s where I’ve bought my lenses) if I can find any so older models don’t matter, I’m just really unsure what would be compatible. 
Thanks for any possible help!!

[kvbarkley]

If you want to guarantee compatibility, but don't need Wireless Master capability - you did not indicate how much flash power you need... - Any EX flash will work. A 430EX would have the most capability, but a 320EX will get you a basic flash.

[shadowsports]

This is from the manual, but as kvbarkley stated, others (newer models) might now exist.

.

[Waddizzle]

My standing advice to people who are not familiar with a type of item offered for sale on eBay is not to buy from there and look elsewhere.

The used camera dealer KEH has several deals on Canon Speedlites in various conditions, from non-functional to fully functional in mint condition.