Converting a carport to a bedroom questions

My wife and I bought our house in Nashville earlier this year and are already thinking about adding on to it. It seems like converting the existing carport to a bedroom could be the best idea and relatively inexpensive since the foundation and roof are already there.

Pics: https://imgur.com/gallery/CMzMP2Z

I am also thinking that it would be nice to have a full bath, possibly where the storage closet is, but I realize that complicates the situation a good deal.

Anyone ever attempt something like this? I know prices vary wildly, but does anyone have a ballpark figure? I’m thinking it could be as low as $10k without the bathroom, $20k with the bathroom.

Also, am I correct to assume to foundation and roof can be used for this expansion?

We would not plan to expand the hvac system to it, probably just have a window AC unit and a space heater.

Thanks for any ideas, advice, suggestions!

Edit: I should mention that we would most likely keep it as a separate entrance from the main house. That way we wouldn’t have to build a hall way entrance. Also it would allow to have a separate room that could be used as an Airbnb.

Source: https://www.reddit.com/r/HomeImprovement/comments/a0n3ar/converting_a_carport_to_a_bedroom_questions/