User blog comment:Badpeteno/Pete's Dungeon Log/@comment-9374256-20130601064051/@comment-9946604-20130601232406

You can buy out chapter's 3 and 4 with gems without completing earlier chapters (90 and 120 gems), but realistically I don't think this can be beaten without any gems.

Each quest has 3 requirements. 1 is a resource and the other 2 are chores. The chore requirements for all quests are totally doable in a reasonable amount of time. Chapter 1's resource requirement is gold-- in my case about a week's worth. 2-4 require food-- MONTHS AND MONTHS WORTH. Enough to get several dragons to 30.

Try this:  for each quest, do all the 'chores' to get the buy out as low as possible. For chapter 1, I got it down to 31 gems. I'd estimate 1/3 of the starting cost for each is as far as you can push it. Next, do surveys and sign up for silly stuff to earn gems. I was able to earn almost 60 gems in 2.5 hours. This is way less than my normal rate of pay, so I opted to just spend the cash.

DONT USE YOUR REAL EMAIL ADDRESS AS YOU WILL GET TONS OF SPAM. I have an email I use just for Dragon City. It's gotten about 400 emails in about 6 weeks.

I'm working on rewriting this log into a walkthrough that will include strategy suggestions and estimated buy outs after chores. Keep an eye out for it, probably 2 or 3 days (every day it takes, the less valuable the info becomes).