Adaptive Reuse is a process that adapts buildings for new uses while retaining their historic features. We have seen this in an urban setting for many years, as in the example above. A condo community in NYC.
We are now seeing more of this re-use in residential homes. As in shipping containers being used for room additions. Check with a progressive architect in your area to discuss your options. It could cost you much less than you think for an extra 700 sq feet of living space. Or maybe you can afford to do something with that lake lot you have been holding onto.