Codes don't make or break new technologies -- new products are tested and proven to meet code every day, but very few are breakthroughs -- and none are breakthroughs because of meeting the code.The other thing I'd mention carries some irony on a site like BP, and that's the power of the real estate market itself, and it's effect on new products. 

It's a 1978 mobile home and insulation is very bad, so I feel somewhat responsible to offer a more cost effective heating option.

I just put a $14k dual HVAC system in a split-level home because it was the only way to really effective control the climate...I think there is a balance somewhere, though.

I tried a lot of paint types, techniques, and colors to get the granite marbling sort of effect.

My goal of joining this forum is to learn and understand how does the Real Estate business works and what are the different and effective ways of finding good deals. 

Search BP for "blanket mortgage release fee".If any are subject to an existing mortgage, do those separately issues that could arise don't need to effect your entire deal.Read the seller financing posts, get a "loan servicer" search that and read.

@Hattie Dizmond   to play devils advocate that's all well and good for you.. but what about the poor out of state investor who was never told of these issues ..

Do you experienced marketers have any advice on whether filtering by tax delinquent homes is even that much more effective?  

Hard to find foreclosures that are cost effective to rehab. 

The main thing that comes through in her post is that she is advocating approaching your new tenants with respect but also being clear about your expectations.