That gets rid of the bleeding and preserves your credit for future investing.

She just needs it gone in order to help preserve credit rating.   

If you lease up the other space you could cash out refi likely at 75% ltv with a larger value.Why can't the lender just release the other partners off the loan and you preserve your cash??   

Plus, in 15 years we could sell without being taxed heavily on the gains…Thus, I think we will max out the capital, rather than “preserving” some €50 per month in cashflow…

We buy great properties, that attract great tenants, that also appreciate higher than inflation preserving our cash flow long term. 

Here's a link to the registry: http://kcmo.gov/neighborhoods/neighborhood-preservation/rental-property-registration/I'm not sure about the other municipalities because my property is in KCMO. 

I completely understand the need to preserve rental housing but empty units do no one any good.

And Capital preservation and liquidity should come into mind as well.

For many people, capital preservation is more important than the return.

If at all possible, preserve the existing column and strengthen it, move the duct off to one side and sister the columns on both sides, if it has settled, slowly jack up back to level - slowly here means like 1/8" or 1/4" every few days - look into structural epoxy systems as well.If you are not sure, consult an engineer.