oh dear..... I never ever decorated a room a child wanted, my standard answer was... sorry no.... you can buy your own house and paint it what ever color you like, they only had a say in what color curtains.... and bedding, nothing else..

Aergia choose blue and after a year she hated it, I simply laughed and said tuff, you will have a blue room till you leave the day (see she convinced Daddy to paint the walls blue behind my back which he did)

Deigma asked for white walls, but he wanted RED curtains with black bedding... I had no problem doing it, when we moved out Aergia wanted to take over his room and I said NO.. heck I pay for half the house, his room got turned into a spare bedroom and SO supported me on this.

Now your furniture is not clear, if it's melamine furniture, you will struggle getting it painted like wood, dark green is not easy to cover up,
primer is light white and it's difficult to paint it like wood... I would leave it that color and tell them NO, decorate it around the dressers...

you can do it very very classy with the white walls now, you can use shades of white and grey on beds, even black and white.... look at zen rooms a bit, on the dresses a nice holly bamboo.... it's totally different but very mature

Let them each pick a color. Use pillows and pictures and bedding to give them the color they each want and do everything else like the black and white. I know it may look a little odd but hey it is easy to fix down the road.

I have redone a a tv hutch and a clothes hutch. Both were stained and coated and I painted them. I had to sand them down especially the first one as i was going form a really dark stain to a cream color.

You will have to strip the existing paint off to see what is under it. It may be stained and depending on that color will depend on the stain you will need after that. They make like a black stain that is pretty nice. It is a project to re-do all of that. Go to lowes and find a middle paint stripper you may have to apply and scrap a few times.

Best of luck.

Take them shopping in the "dorm" section of Target or a Canadian-equivalent store. The dorm or college section has a lot of basic colors that match black and white (since dorms here are very bland), and the stuff is cheap. There tend to be a lot of similar patterns in different colors, so you may be able to pick a themed desk/chair/comforter/pillows but each get their own color. Plus, if they don't destroy it, they can take it to college (actually, I would make it a requirement that it doesn't get destroyed so that it HAS to go to college).

I wouldn't put too much effort into this, though. In 5 years as a teen living with my parents, I floated from Lizzie McGuire pinks and purples with sparkles and crazy designs to overly religious where I wanted muted, conservative colors to Avril Lavigne punk with crazy animal and bright skull prints on white and plaid overlays to super goth where everything was black, red, or another depressingly dark shade of any color (god forbid I be seen in any color brighter than blood red). If my parents tried to keep my room up with my changing tastes, they would have spent a small fortune. I think it's perfectly fine to paint the walls white, keep their dresser whatever color it is, and let them accessorize their beds and walls on a budget. If you don't offer the Hilton, they'll be fine with the Hampton.

Have them both make Pinterest boards and pin anything they like on pinterest to the board. Usually you'll see they tend to develop a "style" a color, you'll see the same or similar things throughout and you base your color/décor choices on the stuff on the board. That is how I did my whole house.

That is a lot of furniture to refinish. As it was your mothers if you plan to keep it then make it the way you want it. Then use it in the guest room in the future. Or if you have a guest room now switch it over and get each girl a IKEA type closet unit that will hold all their clothes in one unit.

I have a small dresser that was my moms that I refinished years ago. I totally sanded all the old finish off. I hate using chemical strippers.

You could paint over the green to do a faux wood grain finish with the faux wood graining tool. But with that much furniture I would not want to take it on.
Can you find a local refinish shop and get an estimate to have it done?

When my daughter was a pre teen she wanted her room done with blue walls with clouds all over. I thought great, I can do beautiful clouds. We got started on it and she wanted clouds that looked like a print on pjs. Not wispy natural looking clouds. I gave her what she wanted and the room stayed that way til she was grown up and I sold the house. It was an improvement over the old wallpaper at least.

Unless it's a very good dresser, it'll be very difficult to remove the green, or cover it well (I painted a lovely dresser blue then regretted it - refinished it and there's still blue in it. And it took FOREVER.).

Option: Paint it white or black if they want that theme.
Or, find a dresser that's wood on Craigslist or at the Thriftstore or garage sale. Then donate the green one.

How old are your DDs? Are they very young or plan to live with you in adulthood? I am not sure I’d spend that much energy on all this if they are leaving soon. I had nice bedroom furniture set for DD in her bedroom but wouldn’t go crazy repainting things. She left for college right after high school and never lived home again (she of course visits). Unless DDs are little girls, I’d think about how long are they planning to live at home?