by testcranker
I almost never build the shipping line any longer. It's too much in terms of resources that can be put to more productive use.Sometimes I will buy the Ironworks, but that is often to avoid it being taken by an opponent as much as it is a method to avoid building costs. It's often a pacing item for bricks.
The Colliery is a 50/50 deal with me, build or buy.
The marketplace I will almost always buy.
Regarding the OP: Money in the early game is tight, grab the offer, build and sell are about the only ways to aquire cash. Loans as discussed are also a good way to have some cash flow if yo manage them correctly.