Need remodeling advice

[Rmk9785e]

Greetings,
I'm helping my daughter with the remodeling of a 30 year old condominium. There are a few plumbing related questions where we can benefit from the expertise on this forum.
1- Do the bathroom/shower valves need to be replaced while we have the walls open? They have been working fine but just wondering if the current models provide significant benefit. If changing is advisable then which brand/model is preferable?
2- We're changing one of the bathrooms from tub/shower to shower stall only. The walls will be quartz slab. What would work best for the shower pan?
3- For a seat in the shower, should we have a fixed seat or one that can fold up?
4- We wish to replace the dual knob lavatory faucet with the single handle one. The knobs are 8" apart. Is there a base plate that would cover the outer holes in the cultured white countertop?
5- We're considering two faucet models for the above, Grohe 32642EN1 or DANIKA L84733. Which one would you recommend?
6- The old kitchen sink has an air gap device installed for the dishwasher. Is it necessary for the new LG LDF7551ST dishwasher as well?
7- Is there any reason we should replace the water shutoff valves for sinks, lavatories etc?
I know I have asked a bunch of questions in one post. Your consideration is appreciated.

 

[hj]

1. That is up to you and as far as make and model, ask 10 of us that question and you might get 10 different answers.
2. work with your tile installer.
3. That is also a personal preference, but a built in one usually looks "neater".
4. None that I know of, unless you use a kitchen faucet that does not have a pop--up mechanism.
5. which do YOU like best.
6. Whether it is necessary or not depends on you local code, not the make and model of the dishwasher
7. Why WOULDN'T you as long as everything is being taken apart anyway?

 

[Sponsor]

 

[Reach4]

4- We wish to replace the dual knob lavatory faucet with the single handle one. The knobs are 8" apart. Is there a base plate that would cover the outer holes in the cultured white countertop?

How about putting in a soap dispenser on the right and a lotion dispenser on the left?

While reverse osmosis water faucets are more common for the kitchen, you could put one in the bathroom. When used for cleaning, RO water dries spot free. OK... not likely that you will want that idea.

Farther afield, maybe you could build in a Waterpik into one hole by adapting http://www.waterpik.com/oral-health/products/dental-water-flosser/WP-480/

Just ideas.... not full suggestions.