Thanks so much! Yeah this was one of the problems with not having the full jam time and being a solo dev, I plan to add building prices to the description for now, and when the jam is over it'll be in the full game on the buttons.
As for Income, it's a little complicated. The steady income comes from houses, the more houses the more income. However, the income only applies at the start of the next build phase, so placing down a house in the middle of the phase won't immediately start earning money, glad you enjoyed it otherwise :)