Safety, no open flames or risk of gas leaks.

If your biggest thing is safety, I'd talk with the neighbors, and tell them you'd like to build additional safety measures and improvements on the portion that's your land.      

I don't know how large your condo complex is, but for condos of 50 or more units, it would be a challenge to get every owner to get to it, and properly clean the vents if it was discovered  vents were never cleaned and it could be a safety hazard.I also had special assessments for new roofs, other building wide improvements at my rental condos. 

Now that I have begun researching real estate investing, my interest in home rehabbing has only grown and I could say Im willing to leave the safety of my welding job in order to gain the skills and knowledge of the contractor field.  

POS requires only safety compliance but as a rule, houses been updated to much higher standards than POS requires

I don't know what's going to happen, but with where we are in the cycle, I would be concerned with safety of principal.

I work as a fire fighter, so I know the reputation of Lake Edwards quite well and intimately from a public safety standpoint. 

There is only one situation that I can think of where I would even consider a tankless and that is where the current water heater location is no longer suitable (i.e. you need the space, or there is some safety concern).  

If it is a rental add some treads for safety.

Unfortunately, many people are taking razor thin deals that are just begging to blow up in their faces.