1. The expense reports either literally killed him or perhaps caused some other negative termination like losing his job. There must have been something wrong with them, perhaps he was committing fraud, or perhaps he had too many difficult expense reports to process so his workload was too heavy? 2. 'Our deal' means the speaker had an agreement with the man that it was the speaker's responsibility to revive him, with the implication of 'up to me' that the speaker is the only one with that responsibility. 3. Your translation is correct, but to 'pimp something out' has a sub-meaning of excessive expensive decoration, possibly even in poor taste. 4. A crossbow range would be a dedicated outside area for practicing shooting a crossbow, as in archery. This would be a pretty unusual area to have, but he mentions a farmhouse so presumably he lives in a rural area with a large property, and likes to target practice with his crossbow.

In response to your follow up question, 'did him in' is a slang expression for, usually, killing someone. 'It was the alcohol that did him in' if you were describing someone who died from over-drinking. But it can also be used for emphasis in a less fatal situation, say someone who was struggling with their job and was given even more work such as processing expense reports so that they had to give up and quit. You could say 'the expense reports did him in'. I think this expression is probably a bit old-fashioned and not something that would come up commonly in conversation. I'm sorry, I don't know the technical grammar words to describe the function of 'in'.