Maze explanation is here.

Startbonus: 400 coins

Collections: 600 coins every 8 hours (19800) = 20200 coins.

The total does not include coins we can get from quests or dragon tv.

For Collecting times check this.

*Dragons:*

Thief -R- #202: The path costs 750 coins.

Key for Diablo on step 9 (380 coins).

Diablo -VR- #1427 : The path costs 2585 coins + 1 key = 2965 coins.

Key for Augmented on step 19 (1970 coins).

Augmented -VR- #731: The path costs 2605 coins + 2 keys = 4955 coins.

Key for Infernal on step 14 (1600 coins).

Infernal -E- #1292: The path costs 3800 coins + 3 keys = 7750 coins.

Key for Chains on step 8 (580 coins).

Chains -E- #1150: The path costs 4035 coins + 4 keys = 8565 coins.

Key for Pyre Magus on step 16 (2590 coins).

Pyre Magus -E- #1321: The path costs 6525 coins + 5 keys = 13645 coins.

Key for Coven on step 14 (1885 coins).

Coven -E- #1426 : The path costs 6700 coins + 6 keys = 15705 coins.

Key for Decay on step 21 (5525 coins).

Decay -L- #1035: The path costs 10440 + 7 keys = 24970 coins.

No key:

Masquerade -L- #1264: The path costs 28900 coins.

Time limited:

21.-23.: Hypno -R- #208: The path costs 7850 coins. This path has food.

23.-25.: Wolfreeze -E- #489: The path costs 2590 coins. This path has puzzle moves.

26.-28.: Space -E- #282: The path costs 5300 coins. This path has flightstamps.

27.-29.: Burglar -L- #756: The path costs 9500 coins.

27.-30.: Alchemist -L- #1425: The path costs 9895 coins.