Stolen money was absorbed by us and the empty houses that were never completed were left to disintegrate.  

It could not only disintegrate the European Union but also start a chain reaction of currency devaluations similar to that which lead up to the Great Depression.

If I were you I would bulldoze the place now and save some money on the taxes till you are ready to rebuild or mortgage the place to the hilt and invest the money in other properties.I would be happy to let it disintegrate into the lot for decades if the money was earning it's keep elsewhere.

On a different property, the units with concrete steps disintegrated and will soon need replaced as well so I'm not really wanting concrete steps unless they are more durable in some way.

Also glass disintegrates  in the hands of a renter. 

Appears to be super durable and certainly will never disintegrate.

Old houses have cast iron pipers that will disintegrate (because of age and/or foundation shift).

Whereas toilet paper disintegrates right away, the "flushable" wipes, when getting caught up in roots, stay mostly intact for a considerable time. 

Over time the casing tends to disintegrate and wires touch, causing the electric to a, cease to work and or catch fire.

Old houses have cast iron pipers that will disintegrate (because of age and/or foundation shift).