Can you post your existing plan? Have you had a vetted builder price it for you? The garage location is questionable if it makes it a long haul with groceries to the kitchen. Does your neighborhood support the level of work you are planning (potential resale if that’s a concern). With the work you describe it’s not just numbers of bedrooms and baths it’s the flow of the home and how it actually works that makes it successful or just a ‘hack’. It may make more sense to keep the garage side as is and adding an en-suite to the bedroom side (what were you planning for driveway work with a new garage location -that seems like a lot of dollars not wisely spent). But seeing the whole plan would help.

Sounds interesting, but why the need? Connecting an existing bathrooms to a bedrooms could make sense because you are making two on-suites.

No answers, but some important questions and observations:

- If you add these bedrooms, will it make your house bigger /potentially better than your neighborhood? You never want to have the biggest /most expensive house in the neighborhood, as the smaller /less expensive houses will bring your value down.

- How often will you use these bathrooms? Said differently, how badly is the extra bath needed?

- Would it be possible to create a Jack-n-Jill type space anywhere? Showers /tubs don't aren't used that many hours of the day.

- Budget choices: Shower pans cost less /last longer than tile floors. Shower curtains cost less (and are easier to keep clean) than glass doors. Linoleum floors are perfectly acceptable -- and are warmer /softer underfoot.

think about how each bedroom guest space will use the bathroom, double up? need a private one... I have 5 toilets in a two bedroom house... only two full baths, but I do have an outside shower as well for summer use. Think it through... Measure twice, cut once.

All is idle conjecture..until you post a floor plan of the existing condition, with every and all dimensions, wall , windows, openings feet and inches. Both living floors.

Add jpegs for all above and show the exterior of the house as well.

Much depends budget, your reasons, potential length of stay in the home as well.

Additions and alterations to a home ALWAYS cost more than homeowners anticipate. It's not uncommon for our clients to "value engineer" projects after a final budget comes in.

Bathrooms equal $ and its always more than you think. They also gain $ on resale. That said I would always keep a powder room. Always. If i were doing anything I would do one complete additional bath to serve the new garage room and not omit having a powder room. A guest doesnt want to share their bathroom with the household.

Do NOT add a shower to a powder room. It morphs to bathroom, and a mental mind wah wah of how to hide the bathing.: ( Drives me insane when a builder does it next to "flex space" .Commit, and its one or the other.

We can only guess. We need ato scale plan of the house as it sits now , then one with the addition added . Garage conversions are of expensive becuase the garage is not living space as it is and adding bathrooms are also pricey . Where I live the garage will need to be ripped down and so really an addition is what you are doing.. Also codes in your area decide if this additional space is allowed . So a bit more info and those plans are a must for help here.