I would go plan 2 but swap the bath and shower enclosure

It is not the largest of spaces, so I would recommend a Square P or "Scurve" bath with shower screen and shower over immediately on the left when you enter the bathroom, the WC on the left wall when facing the window and a run of units with basin on the opposite wall. You'll have a far more comfortable space and room for more storage. Use the money you save on the shower tray and enclosure on really nice furniture, fixtures & fittings and a beautiful shower - you'll achieve a far more luxurious, spacious bathroom for a similar price! And with a little of the saved cash, splash out on a lit bluetooth mirror, lie back and relax in your own mini spa while listening to your favourite sounds....

Hi Kelly, thanks for the additional info - it always helps in order to advise on best options for any given situation. You make a few important points which have a bearing on the best way to go:

1. Your knees dictate a strong desire for a shower
2. It is not your "forever" home
3. It is a home which, for resale, needs to appeal to a family

If it were your forever home, I'd suggest ditching the bath and getting a really good, large walk in shower and spend the savings made by dropping the bath on really good fixtures & fittings.

If getting in and out of a bath-shower precludes it, then I'd propose the layout mocked up below (please excuse the generic units and colours!):

1. Avoid the shower crossing the window at all costs - it will only bring you problems, especially in an older property with different construction and poorer insulation
2. As a "young family" home, you must have a bath, and make it as easy to access as possible for a parent helping a baby in the bath - mount the taps under the window to make them easy to stretch to, and keep plenty of "kneeling room"
3. Go for a quadrant (curved) shower - it will open up the area as much as possible, improve flow and doesn't lose any appreciable space. Max dimensions I'd go for are 800x1200 if doable behind the door - you'd need to measure accurately
4. If you are able to squeeze in a standard 1700w bath at the end (if plaster is being redone, it could be chased in) then great - otherwise a 1600 is perfectly liveable when you also have a separate shower
5. Use a wider, narrower depth slabtop basin unit - the one I've shown is about the maximum I think you can comfortably do at 400d x 810w, but I'd recommend perhaps a 350d x 600w like the Mereway Trend Simplicity basin
6. As a family bathroom, think easy clean/maintenance - large format wall tiles with minimal grout lines, possible shower panels in the shower, perhaps a Palioclic floor.
7. Don't break the bank on doing up the room, as you've already indicated you're likely to move before too long and as a "starter home", there we be an upper limit to the value it would add. That said, if you pick carefully, you can get some really good value flooring, tiles, fixtures and fittings which can make a modestly priced bathroom look considerably more luxurious!

Hope these ideas help - feel free to use the images/plans however you see fit!

Oh, just to add - I would avoid the "mobility" baths - fine in a retirement bunglow, but would be a real turn-off to a family. And as you rightly point out, they are horrendously expensive (I can never understand why) and are a pain to use - staying in the bath getting cold while they drain below door level, leaks (they do happen!), lots of little nooks & crannies to clean.

I'd steer clear if I were you!

You're welcome!

I think Caldicot's idea is a really good one if you're comitted to a separate bath and shower. Personally, I'd prolly go for a shower over bath + massive sink and lots of storage where the cupboard was - ideal for towels and bed linen.

option b looks good to me, don't want to be looking at a toilet through the doorway everytime I pass it, so shower or bath would be much better there, and get rid of cupboard to maximise space, have some open shelving a la ikea instead... :)