I would investigate.The rockwool insulation your friend suggests, the stuff made by Owens Corning, is called Pure Safety.

I have found that duplexes rarely make sense as a pure investment property.

In NNN in most cases you won't see more than 2% rent bumps annually but you also have no cost with NNN so it's a pure gain.

Generally speaking, the property taxes in the areas I've mentioned are around 2.5% of appraised value (the joys of no state income tax?).

Fire him,pure and simple.Any agent to busy to deal with me is too busy to be taking my money and they get canned.Too many other hungry,less busy agents who need your money desperately and will give you the attention and level of service you deserve.It's business,keep it professional.Maybe you are doing him a favor and reminding him never take a paying client for granted.

All of them are pure garbage. 

My friend got similar advice to what you are getting of 'dont sell more, youll have to pay more taxes' - which I think is pure garbage IF you have a better use for the money.

The only way I'd buy a pure rental like that is if I could build myself a substantial equity cushion through forced appreciation, much like a flipper would only hold after rehab ... then you'd have a solid appreciation return early and could likely improve cash flow that way as well.

Fortunately, we have very little debt and one of our rentals is fully paid off so that income is pure residual.  

I found this info through pure elbow grease.