Belmarniss needs a lot of money, spread out over a fairly long time, before she's ready to call it the hour of their expedition to the surface. Strawberries, potatoes, herbs, peanuts, spinach, rhubarb, all the things drow grow in heavily guarded densely green caves with each cave needing a dozen Lights to let the plants get enough.

She has to buy fancy defensive gear, first, and let it be known to everybody who might be watching them that she's doing that, and then she can start loading up on useful things that will help on a journey and would be tempting to steal, only after they have enough obvious firepower between them that nobody would be stupid enough to try to steal it who can't afford to get their loot from a softer target. It's mostly in the form of scrolls, leaving it ambiguous which ones she's scribing into her book and which ones she's keeping in her beaten-copper scroll case to pull out on an assailant. (Share Language is one she puts in her spellbook; Waltana's done a good job of learning to speak Drow the hard way, and just a couple of castings of Share Language will polish off the remaining confusions, at least about grammar and common homophones even if she doesn't come out of it with a first-class vocabulary, and sharpen her accent. Then they can start in on Taldane, because Waltana's going to need to be the one to do most of the talking, in Taldor.) She also gets them adventurer clothes, busy visual messes of silk suitable for stowing wands and components and weapons in, a deep anti-sunshine hood on a cloak of resistance for Belmarniss, magic gloves that let Waltana cast mage hand and prestidigitation herself, all of it making them look like serious business to anybody who's assessing that by sight. Healing potions, because they don't have a cleric and probably don't want one given the selection available. A bag of holding, because they want to take most of the equipment except for the non-Shroomy plant growing objects, which they can sell for last-minute purchases before they leave and allow to deteriorate once they're long gone. Bedrolls and camping gear. Tents aren't really a thing, downstairs, they'll be sleeping rough for a while when they first break out onto the surface, but Belmarniss breaks through to third circle with all this skulking and studying, learns Tiny Hut.

She doesn't really talk to Waltana about how her negotiations with her family about her decision to pick up and go adventuring with her alchemical barbarian pal are going. It seems like it's probably mixed.