You had me until "pain meds" (sorry if someone posted this already, I didn't read all the way through).. not saying it's a deal-breaker, I'd just be super careful and already have a solid back-up plan in place.

The the boiler is natural gas so I am looking for estimates on how much it would cost to install new gas lines, a new boiler, and then a second breaker box etc for the electric to separate the utilities amongst the apartments.

The water service lines need to be inspected as well and if they are galvanized that would be a deal breaker for me (unless the price is real sweet) I mean this is probably one of your biggest investments if not the biggest.

You would also still have a fuse box, unless it has been replaced with a breaker panel.On the plumbing side, your main drain lines and stack are likely cast iron and would be 70-75% through their serviceable life.  

All of them ended up in extensive litigation all the way up to the Third Circuit Court of Appeals before it ended up settling. 

More than anything though, since you can always learn the knowledge pretty easy, I think your big deal-breaker will be the fact that you are in Vegas.

I know I passed on a house that would have required a new breaker box for electrical due to this.Mortgage Insurance would have killed any cash flow that I might have made, but with the VA I was able to make a little profit.As for finding a 4-plex, well you are on your own there.

You said you had an electrician there so this has probably been ruled out already but a refrigerator usually requires a dedicated circuit or as the get older and less efficient they will constantly trip the breaker when the compressor kicks on. 

That is a deal breaker for me. 

This is a deal breaker for me because I believe that 6 hours is a reasonable amount of time for a thorough inspection for such a property.