It's not possible to complete the final quest in time without spending real money on the game. This defeats the purpose of Gamekit for me, and I'm sure for other people.

It takes maybe three days to just gain enough resources to upgrade the palace (as you need to spend a lot upgrading other buildings first), and even with all the in-game boosts I've earned to skip time or add resources, it's just not possible.

My palace is level 12 and I honestly think I'd need two more weeks at least to have enough resources for the final three levels.

I thought it might be worth sharing this info here for anyone trying for that final level - you'll need to spend cash if you want to complete it, I'm certain.