A quick fix to revert housing cost back to old values. It was too difficult (almost unplayable) to recover from negative income.
Change log:
-Housing cost has been reverted back to 0 gold and 20 wood (from 200 gold, 10 wood)
-Stone walls can now be built over wooden walls. Will salvage the cost of the wooden wall (25%).
-Building a gate over walls will now salvage the cost of the walls (25%).