Maze explanation is here.
Startbonus: 400 coins
Collections: 600 coins every 8 hours (7200) = 7600 coins.
The total does not include coins we can get from runner, quests or dragon tv.
For Collecting times check this.
Dragons:
Flame Knight -R- #1199: The path costs 860 coins.
Key for Troglodyte on step 9 (460 coins); Heroic Quest Chest on step 7 (255 coins) and 10 (580 coins).
Troglodyte -VR- #210: The path costs 2825 coins + 1 key = 3285 coins.
Key for Atlantean on step 16 (1915 coins); Heroic Quest Chest on step 13 (1335 coins).
Atlantean -E- #378: The path costs 3630 coins + 2 keys = 6005 coins.
Key for Bard on step 19 (2435 coins); Heroic Quest Chest on step 11 (1055 coins) and 22(3085 coins).
Bard -L- #1457: The path costs 6020 coins + 3 keys = 10830 coins.
Heroic Quest Chest on step 16 (3185 coins), 19 (4485 coins) and 20 (4970 coins).
Faze Rug -L- #1461: The path costs 8165 coins;
Heroic Quest Chest on step 21 (6350 coins) and 23 (7535 coins).
Timelimited:
22.-23.: Draek -L- #656: The path costs 6720 coins.
Herioc Quest Chest on step 20 (5060 coins) and 21 (6150 coins).