I have tried Rentredi on a BP Promo, it is horrible. 

Gather emails with something like Stayfi, use a qr code to have guests follow you on socials or leave their emails in a sign up for discounts coming back, use a Meta Pixel on your direct booking website or landing page and then do a retarget ad campaign to them, offer "Family and Friends" promo codes to guests when they come back through an auto message a couple of weeks after they have left, etc. are some that I use.  

My local code enforcement officer is happy to take calls. 

I also did a local renovation in 2022 bringing it up code.

It sounds like you have an un-permitted unit, which is essentially always a risk since there has been no notice to the AHJ that it exists and they can therefore initiate a code case to have it removed in most cases.

I'm showing the FMR on this is $2,000, which is listed by Zip Code here:Am I missing something? 

I then called the customer and told them their agent needs an education , of course the deck isnt up to todays code , code changes every year . 

As U.S. citizens residing in Europe, we are required by the local tax code to hold the property in our personal name.

My question is why you want to bring it up to code, other than just to feel good or improve your exit strategy?

I was thinking of starting a rent increase for my 1 bedroom tenant voucher due it being low and well under fair market value(Based on  hud and zip code) but my tenant is in the process of having a caretaker for her disability and getting approved for a two bedroom voucher.