Been wanting to finish this game for a few weeks but last time I played was after getting stuck on the boss for chapter 8 (I think). The one everyone considers as the hardest fight up to that point.
What are some good spots to grind out my classes to prepare for the fight? I want to say I was around level 40.
Still have a hard time getting enough cash also. Only have the one skell and trying to finish the chapter I'm on so I can finally get the flight ability.
You'll have more fun doing missions rather than trying to level grind, to be honest.
If you must grind though, check your skell weapon inventory and see if you have a Right Back weapon called a G-Buster or a Right Shoulder weapon called a Phoenix. If you don't, there are level 15-20 puges (the Star Wars droid looking robots) in Oblivia that I think drop level 20 versions (equippable on the free skell). The puges in Badr Basin drop level 50 versions and the ones in Bedrock Hold in Primordia drop level 60 versions. You can buy level 30 G-busters at the shops.
These are powerful, if fuel-thirsty weapons that make short work of most non-boss enemies in those tiers. Phoenix is especially handy for getting rid of mobs of enemies, because it hits everything within a damage radius of your skell (above and below too) three times. With those equipped, you can take on higher level enemies and jack your levels up pretty quickly.
As for money, how much have you been exploring? If you've been finding vantage points and unexplored territories, these count as "sightseeing spots" and these are tied to the nearest miranium probe location (look at the description of each probe location and it'll say if any sightseeing spots are tied to it). These sightseeing spots massively increase the amount of potential revenue that probe can generate and are more important than the letter rating. A D-rated location with two sightseeing spots generates more income than a B-rated spot with none.
Puy research probes in these locations once you've unlocked those sightseeing spots. Also remember to link probes of the same type if you can and take advantage of duplicator probes. They copy EVERYTHING that's going on in adjacent probe locations and ignore what's going on at their own spot, so it's best to place them at "crossroads" near multiple other high revenue spots so they're copying more than one good research probe at a time. Duplicator probes are also compatible with booster probes, so you can get huge revenues with the right placement. I'm currently pulling in nearly 300K per haul.
The other thing to keep in mind is that mining probes drop your revenue by a lot. You need mining probes for miranium and miranium eventually becomes more important than money, but at this stage, any miranium you bring in over your storage limit is wasted. Basically take out any mining probes you don't absolutely need and replace them with basic probes and you'll see your revenue go up.