I get threats of lawsuit multiple times a year and have never been sued over an RE matter.  

Yes unfortunately lawsuits can be filed pretty much anytime for any reason regardless of whether they are right or wrong.

With that said, I am personally in the middle of a law suite that prevents me personally from being involved (I think?)

It has had many self done additions over the years so going to take about 250K to do the remodel.When all said and done will be a mostly all new 3/3 plus 1/1 in-law suite, and two apartments 1/1 and 2/2.

It only limits the extent that your assets are liable if you lose the lawsuit. 

You are going to have to guarantee the LLC and usually your home, retirement accounts, car and similar "primary" assets have a good degree of protection from being seized in a law suit or bankruptcy situation anyway. 

Who will win a law suit?

What can I do about the appraiser - file a complaint, lawsuit?

We have a large umbrella insurance policy for all of the properties to protect us against lawsuits. 

Tell them you have a great lawyer on retainer who is looking for something to do and you will countersue for a frivoulous lawsuit whereby (yeh, use the word whereby on them) they will be responsible for your legal expenses.