Can you build it later? Do you have DIY skills?

If you really want it, what is the add on to the monthy cost of the mortgage payment? Not much over 30 years. Will you use it?

Picture not showing. Unless the space is attached to the kitchen I wouldn't worry about matching cabinets. Look for a cabinet style that is less and talk to the builder about what is making the cost so high. Sometimes changing a few drawers or using free standing units instead of built-ins in part of the space can help to cut the cost. 8x8 is room for a nice compact very functional office.

Thanks. I updated the post and hopefully the pictures work now.

last question, is the rear balcony required? you could really use the space if its not.

I would not be using it as my office - I will use one of the spare bedrooms. My thought was that it would add value for a future buyer because they might need that extra bedroom, in addition to an office. My primary use for it was the wine rack and fridge :) Any other ideas for it that I could do for less than the $6,500?

You could "outfit" that small room later. Adding whatever furniture you'd like, bookshelves, Bar cabinet with mirror, etc. Reading nook with comfy chairs.

If you're financing this place how much more will the $6500 add to your monthly payment? Then decide if it's worth that amount of money to you.

If you finish it later and just pay for it then you won't be financing and paying interest for years to come. Not a very romantic way to think of it.

well, if you WANT it that changes things; but don't worry about the next buyer, you arent even in yet.

Our specific plot has the rear balcony, but not the front balcony.

The space will be awkward whether you pay for the upgrade or finish it later. You won't want guests in there to use the bar and you already have a good office option.

Have the builder put a door on the space and create an awesome walk-in pantry and storage space.

If you just want the wine rack and frig. only put those elements in. Do not build in an office for a future buyer, if it is something they need they will see the potential of the space. If you put in things that suit your needs, but that are not built in, they can move with you or be sold with the house.

consider a barn door type door to close off the space if you want storage. It would not block furniture on either side.

Okay, since you are in the Bay Area and I suspect your home is well over $1,000,000, $6500 is not much more.
You are getting a very good price, since the workers, material, will be there anyways.
A relative just had a small kitchen banquette built for $7,000 here in the BayArea :)
Labor costs are comparable to home prices. You're in a super hot market, I think it will be worth it in the long run.

Thanks everyone! What are your thoughts on recessed lighting in the bedrooms? I am getting the "electrical package" which puts additional lights in the living room and master bedroom, as well as junction boxes in the spare bedrooms (rather than a single pole outlet). Is that sufficient, or should I spend the $660 per room to get recessed lighting (4 lights)?

Not necessary, IMHO. One beautiful light fixture will suffice. For a bedroom, how often do you use overhead lights? You will need bedside, reading lamps, though.

I hate rooms that feel dim, so I'd go for the extra lights. I still use my room to read/do chores/escape from kids sometimes, ha. Also, getting dressed, looking in mirror, etc- I like that my room has add'l lighting.

I don't think it is necessary, one center light should be enough with additional lamps, but you may want to opt for the additional lighting in the room you plan to use as your office.

Bedrooms don't need recessed lights. You need a closet light and bedside lamps.

All my bedrooms have recessed lighting. There are times when it is needed, such as during cleaning.

I wish our bedrooms had recessed lights. They don't even have a single center fixture. Given my druthers and the budget, I'd add recessed lights to all of them, on dimmers. I hate the lack of light in my bedroom. And yes to decent lighting in closets. We had no lighting in our master walk-in until recently ... adding a couple of flush mount LED fixtures has transformed the usefulness of the space.