Just throwing my two cents worth in here...
In games where PNW is an issue, I always use the same strategy....
When strting the company, I try to start with 80/800. this keeps the number of shares at 10,000.
I'll take out a bond.
Then I will try to buy an industry if possible, especially one that is under priced, and more so if I can feed it.
For the first year I will try to operate just in the red so that my share price does not rise. I want to make it through the first year so it drops right down, and does not appear attractive to other players. I do't pay dividends until I own 100% of the stock.
I will even hold a train from going into station in December so as not to get the cash until the new year.
Once my share price is low enough, I will try to use my cash to buy back stock, and buy on margin. I try to have all my stock by the 5th year. Once you own 100% of your stock, your PNW will always be your company value.
One thing about this strategy is that you can get stuck in a rut and never make it out. Issuing bonds to buy back stock can be risky if you get an F- credit rating for a few years. You need the industry, and it has to be a young one that only start making real money in the 3rd year. That's when you will need to most.
You will need to lay down a route that is complete right off. This is where things get dicey, and I have found many times were I am only able to get the track, stations, and one train with the cash I have in the beginning. Often it will be three years before I get a maintenance facility, especially if I can replace a train for $50k.
If buying an industry isn't an option, then the best money maker is to plop a paper mill right beside some lumber camps... At least two. It will begin making money right away, and then you can follow up with track when you can. Buying and building profitable industry is crucial to increasing your company value, and in turn your pnw. Unless I have to take over other RRs or want one for another reason, I generally don't bother buying other company stock until they are below $10.
It takes time to figure out the exact right strategy when starting a map using this method, and I tend to start a few times before I get it right. But then I play right to the edge, and will scrap a game if someone buys any of my stock.