So our new renters moved into one of our units on the first of July, since moving in, they have had a laundry list of items they are requesting to fix. 

Have you thought about trading the fiveplex for a Class B duplex in a Class B neighborhood and move into one of the units and rent out the other??

I moved out here almost 7 years ago and have lived (rented) a significant amount of time in all areas except for the center (Utuado, Ciales, Jayuya, etc.) of the island. 

That's an incredibly long time for a home to not move.

When did you move to SA?  

Tenant just moved out, cleaners found they used the wrong type of cleaning product on the stainless steel appliances, causing a permanent discoloration. 

The current owner is getting older and needs to move back home (according to family) towards my hometown.

Unless the people were significantly value oriented (think super cheap) 95% of the time they would move on to another location over taking the double beds.

Do you recommend me buy a house to fix or buy another house new for me and use my current house for rent and move to the new one?

I am trying to see if I can use a separate business bank account for each security deposit and avoid all the paperwork with W-9s.No need to suggest move-in fees - I am only interested in doing security deposits at the moment and am very familiar with Chicago RTLO.