The original finish is almost certainly lacquer for this period unless someone has refinished it in their basement. Lacquer has the property of re-melting itself and becoming a single film finish. First clean it (see the link below). For the chairs, I'd recommend getting some aerosol lacquer. Deft is a commonly available brand. For the table top, it's a bit difficult to get an even finish with aerosols. Deft, though, also makes a brushing lacquer that you can brush on a light coat or two. I'd also scuff sand it a bit first to even out the wear areas. Just enough to dull the surface. The only possible problem with this procedure is if the original owner used Pledge (or any polish containing silicone oil) on the piece. It messes up the surface tension of the finishes applied over it and causes them to fish-eye. There are cures for this, but I'm not aware they are DIY level. If you have spray equipment, you could also get canned lacquer. But I'm assuming if you have this equipment, you probably wouldn't ask this question. (An observation, not a criticism) Here is a link that might be useful: saving the finish.

I've done a few pieces (a buffet turned bookcase, banquette, dresser and nightstand) and I'm about to do a new table (yeah .. new but purchased at an outlet store ... don't like the color) all with high quality paint (either Fine Paints of Europe Eco Satin or Ben Moore Aura) and an awesome brush (Omega, available from FPE) and I've been thrilled with the results. Nary a brushstroke in sight. It may be a different story when I attempt the table which will require very LONG brushstrokes, but I really think it's all in the paint. As long as you use a good paint with great self-leveling characteristics you'll have a nice finish. As an alternative to spending a lot of money on tools you may not use again, have you looked into having it professional sprayed? I have no idea how much that costs, but it might be better than investing a lot into very specific tools. That table is going to be gorgeous, by the way.

I used BM seapearl on the walls when I remodeld my master bath last year. I wish it was a bit more beig-y than yellow-y, but it is a nice neutral. Have your friend look at the Roche Bobois website which shows lots of photos of transitional/modern furniture arranged in old traditional and ornate European rooms. If the trim is original and/or high quality, please convince your friend not to remove it. It will add depth and interest to the room once it is made more monochromatic.

Things to consider in your stairs design: build by code or build by comfort? Read what the code says in your area for minimum rise and tread. Based on your ceiling height, the run and width of the stairs will be the minimum square feet. We built with 'aging in place' considerations so wanted our stairs to be easy to climb, that is, a slow rate of rise. This was listed as a requirement for our design when we started working with an architect. We did a rise less than code (we did 7.25") and a tread of 12". Our stairs are 4' wide and the run is 14'1" with 9 foot ceiling height between floors. They are very comfortable to climb. A friend has a 100+ year old house with a grand staircase and the rise is about 6 3/4". Interestingly, that rise feels too low. We used a rise of 7.25" for outdoor stairs, too - deck and garage to house. I kinda wished we had done a lower rise and wider tread on our deck stairs but we had to draw a line on costs since we were using composite decking material. This thread from 2002 has great information on stairs. (It is a little unsettling to me to realize I have been reading this forum since 2002!) Renovator8 has very helpful advice in the thread. Stair Math forum thread from 2002