I know that a lot of attention is given to the query letter formatting -- margins, length, paper quality, etc. But when it comes to the envelopes, do the same rules apply?
Do you HAVE to run an envelope through a laser printer to apply the agent's info and your own info on the SASE? Are return labels acceptable on the SASE? After all, they DO have all of the necessary information. Can the agent's information be handwritten or printed on the initial envelope?
Are these things acceptable, or do they scream "UNPROFESSIONAL HACK!" on sight?

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