Unfortunately due to the position of a window, we can’t do both.... it’s either/or

then have the biggest vanity for the available space..every reno is a compromise and unless you think the extra expense will double the return i would rather buy a bathroom in original condition than pay more for one that has been renovated to suit some unknown buyers..and enlarging the shower is usually much more expensive than installing a bigger vanity but depends on the existing floorplan and finishes

Sorry, why do you have 2 showers in one bathroom, or am I missing something?

@dreamer - that’s the way we bought the house... not ideal!! Now whether to change the format before selling? The ensuite needs attention before we sell (it’s 3 tones of brown) so do we update current layout or change layout....

why not post a flooplan and some photos so we can better understand what you have

I found the photos and floor plan from when we purchased the property 5yrs ago... the ensuite now looks quite tired...

try a new wider vanity with one recessed bowl in the same location...if you can't find an off the shelf vanity consider having one custom made to suit the space with doors under the basin and drawers under the window and add a new spalshback and fresh paint and leave the original tiles and shower as is..a new wall hung vanity will be easier to install in line with the bottom of the window but colours to enhance the existing tiles could be better than my poor 3D image

You have a double shower which is very popular at the moment (not two showers) you could redo the top of the vanity and add a new mirror which starts from the top of the vanity and white shutters on the window might give the bathroom a lift without over capitalizing

En-suite layout is fine, Looks like you have a double hung window with a slightly lower sill to the vanity height. . I’d put a stool in front next to shower screen. Update vanity and top and splash back, maybe lowering mirror. Could put a niche in the side wall if want extra storage. Could change mirror to a cabinet, even if it protrudes, mine does, A smaller basin would increase spaciousness and bench space. Can also increase depth of vanity, to 550. Replace floor tiles if you want but I’d leave shower if you want to keep costs down. otherwise retile to full wall height will improve look.
Could add a pendant light over left side of vanity

And don;t forget the power of paint, I think white with matching white shutters. can you show a couple of recent photos as the real estate photos are always over cooked

Agree with others, you have a double shower, not two showers. A photo of bathroom now, would help. I would always recommend to regrout and re paint. Only replace vanity if it is water damaged. Just keep as is, just freshen up. You said you are going to sell in three years time. I suggest to revisit this bathroom when you go to sell. Then it may be due for a new vanity. (Or not)