I am guessing the installer is proposing a full tear out here and therefore the replacement of the trim is required? What does the rest of the trim in the home look like? If you have a dominant style throughout, do you want to go for consistency in the home? Question will be if that trim is even made any longer. You can go the expensive route and have custom trim made for your application to match the original if it is no longer available, or you can go with a currently available style of trim that you can systematically replace all the trim with as you remodel from room to room.

Trim is a personal choice. I know there are historical norms for this type of stuff, but as long as you are staying inside those normal selections for that style and age of home, there will be several to choose from and you can then personalize it somewhat to what you prefer.

It is very possible both window trim packages are original, many times the trim in the “public spaces” were a bit more detailed than in so called private spaces. In homes we have renovated we have stayed true to the era this is certainly easier if the trim is to be painted. You should be able to replicate the window trim by purchasing real wood at a local lumbar yard, most of the trim is still readily available.

Question, why can't you reuse what's already there?

Why are you replacing the windows instead of fixing them?

The trim in the bedroom is original to the house so should be replaced with the same.

Look into repair of window,or replacement of only the sash. And, even if you were to have to replace window entirely you should not have to replace the trim. An installer should be able to remove it without damaging. If it is damaged, it can be easily milled to match the old. Shop around for installers - some just dont like or have had much experience with older houses and their quirks.

Whether old house or newer, you dont want to end up with a mish mash of different trim, windows, doors. If these arent consistent it starts looking like a cheapskate landlord owned it. Its an unsual profile but note the trim width is about the same upstairs as downstairs - so overall effect is same. It was not unusual to have the fancier higher cost wood downstairs, and more economical upstairs.

For detailed repair info post on thehistoricdistrict.org - professional restorers are on board. Window repair is a lot more labor intensive, which makes it the ideal DIY job. The reason a lot of installers wont do it is simply its not their business model. for them to do it, it would indeed cost an astronomical amount. They can make more money installing new windows. Which is their right - more power to them. However they should not be telling you that its not repairable like its some kind of ulitmate truth. Thats where you might want to seek out a person whose business is window restoration vs replacement, and get their opinion. What I did was hired someone to fix the first one and teach me how to do the rest - not difficult or expensive, just time consuming.

I have a 1920s home with beautiful woodwork and trim - I get wanting to do it nicely. Anyway, we just matched the original (it was very costly to have a key made, to match it exactly, but there was an in- stock window/door casing (that's the wood trim on the sides and top) that was same wide width and many 'grooves" and 'bumps.' I like having the entire house cohesive, so that's why we tried to match the original. Oh - don't go to big orange to find casing. There's probably a millwork place nearby (your GC will know) - go there in person mid-day or afternoon (after the pros are mostly gone) and chat up someone. I got alot of info that way, and it was fun too. Oh - I brought in a sample of my original casings, baseboard, plinth blocks, etc., and he did a computer model to match to his in stock items. (FYI Getting a custom key made - to match the casings exactly - was $1,100 plus the wood. Yikes.)

For my 1939 house, I replaced the wood sashes with new wood sashes. All the trim is original. Of course, they had to be custom made because my windows aren't standard by today's measurements.