Rehabbing Vacant Apartment

[Robert P.]

I am in the process of rehabbing a vacant apartment that I just acquired. Before anyone moves in, are there any things I should be proactive and check/replace, etc. 

I am a first time landlord and hope to get some tips on what people usually check and replace/fix if needed before someone else moves in. (i.e. bathroom sink drain, kitchen sink drains, etc.

I know this is a broad question, but figured anything would be helpful!