2000000 coins are required to achieve Merchant Prince in this fast paced episode. The time frame is short, 1780-1880 AD and there are no other AI merchant players to build additional markets or rails or purchase upgrades.
There are four supply centres which act as import centres for foreign goods delivered to Britain. They are Manchester, London, Bristol and Southampton. Imported goods available to the player merchant at these centres if you build a market include; sugar, furs, tobacco and cotton. Purchasable upgrades will produce rum from sugar, coats from furs, cigars from tobacco and dyed cloth from cotton.
The key to MP is to develop these four centres with each one being the distribution point of a resource to the other three. For examples all the furs from Bristol, London and Southampton are taken to Manchester and redistributed as Fur Coats. London makes an ideal Rum and Cigar manufacturing centre because its market radius usually includes a distiller and cigar maker. All the raw tobacco and molasses available is channeled through London. Bristol often starts with a sugar factory which can be purchased. Southampton is the ideal market to channel all the raw cotton because later in the game this area always has dye its its town radius.
Wales and Northern England should be kept free of markets till you can combine coal and iron.
To achieve MP level follow the pre-game hint to invest heavily in producing and delivering finished industrial products like; Ploughs, Iron Cannons, Rails, Steam Engines and Rifles.
Invest in either Rails or Canals or Coastal shipping, but not all three. You only have 100 years to achieve your goal.
A Rail strategy involves taking immediate use of and upgrading your merchants to Horse drawn rail [cargo 10] and then the Northumbrian [cargo 13] and later the Adler [cargo 16] as soon as they became available. The American [cargo twenty] comes very late in the game and isn't essential to achieving MP. Adler's cope well given the size of the single map.