Buying a house with garage conversion without permits

[Ray Li]

Hi, newbie investor here. I just entered into contract for a single family house, where the seller disclosed that they converted the attached two car garage into an in-law unit without applying for the permit.

1) Is there any legal issues with buying a house with a conversion without a permit.

2) Once I buy the house, if I plan to hold it as a rental, would I need to get the permit for the conversion?

3) If I instead decide to flip the house, would I need to get the permit?

4) How easy would it be and how much would it cost to actually apply for the permit? Who would I need to contact for this? A GC or a city inspector?

The house is in Garland, Texas in the Dallas / Fort Worth metroplex area, if that matters.

Thanks,

Ray