You specifically stated you lived in the property from 2013 until 2018, which makes it clear it was your primary residence. That tells me you took out a standard home buyers type of mortgage, not an investment property mortgage. So I don't see how you can claim it was investment property. Especially since there was absolutely (according to you) no business use of the property of any type during your period of ownership.
Maybe I'm missing something here? It's perfectly possible.
