It's generally advised not to remodel prior to selling. Potential buyers may have different taste than you do so your remodeling choices may not suit them. In that case you have just wasted your money. In my area inventory is so tight every home that is priced correctly sells quickly despite interest rates. Are things not like that in your area? Or is there something non-functional about the bath that is causing you to go down this road? If you must remodel, you will have to post a floorplan and pictures in order to get good advice. You know what this room looks like, we do not. Our imaginations will not be as good as solid information.

Post a drawing for better advice.

Just do a single sink 35" or 48" vanity. I'm not sure I'm understanding the situation right, but it's fine not to have the largest possible vanity!

We need a to scale floor plan to get a real feel for the space . IMO never renovate for resale it is wasted money price the place to sell and move on . This type of reno done in a hurry usually looks like it was done with no plan.

If you haven't done so yet, you can find out from your city hall what needs permits and what doesn't. YMWV.

I guess the Dilemma was solved?