How much cash have you got? If not much, then I would suggest just banking on skills for a little while. At the very least, get the level 5 skills and level 15 skills for most of the classes (sauce, pasta, drinks, crafting) to make things go a whole hell of a lot easier.
Then basementing becomes a lot more fun, because you're not sinking about 3 million or more to a single mind-numbing run.