I'm underwater on my mtg, have been denied a HELOC, been denied reactivation of a dormant HELOC and have medical bills that I'd like to pay so I can make good on my obligation.

Our break-even on this is about 7 years, but we'll probably sell before then so this makes sense.In our inspections, some dormant mold came up in the attic and the seller settled on 3k towards closing costs.

Since these are truly black and white business expenses could I use my dormant S-Corp to run the losses through and just take a 30k loss on a k-1?

I watched people continuing to grow, while I sat dormant.  

If the LLC was dormant for 2018 you shouldn't be filing anything at the federal level. 

My flipping LLC has been dormant, I deposited some money to the bank account and purchased properties.

They would function more as a sleeping/dormant partner.  

If you want a layer of anonymity, hold the properties in a land trust with the child series LLCs as the beneficiaries.Separately, if you do flipping, have a Series LLC for that, with each flip in a child Series-LLC and left dormant after sell.Here is a diagram to help you on your quest: asspro-cya-diagram-v6a-solo-401k

In North Idaho, we get hot temps for a max of 3 months a year so the unit is dormant most of the time and it never gets terribly hot. 97 was the hottest day so far this year with 30 percent humidity.

I'm not worried enough to start selling off the real estate portfolio but my cash is waiting for an opportunity and I have a couple units that are free and clear waiting to be refinanced, quite a bit of opportunity sitting dormant.