Same business category at the same address

I’m currently living at the house registered under my dad’s plumbing company. I’m currently in the process of creating my own plumbing company and was wondering if it’s possible to use the same address for my Google business page. I’d add “Unit 1A” to the address and have “1A” printed on the back door of the house’s addition, but I’m wondering if that’s enough. I can also add signs that say 1A is around back.

If this does not work, what cheap alternatives do I have?