In a previous post I detailed methods for determining the best way to invest your "money" in many of the game apps on Facebook. I worked out a few more details on how to account for some other costs I had not yet considered. That gets complicated though, so I think I will start with the conclusion and give the details later.
Here is the problem: You can buy "lots" that give you a permanent income, and you can buy 1, 5, or 10 lots at once for a fixed price for each lot. The price per lot goes up for every lot you already own, so buying 10 lots at once save money - if you can afford it in the first place. Is it better to buy lots one at a time, thus increasing your income a little much sooner? Or, should you save your money for the big purchase of 5 or 10 lots later on?
Here's the scoop: Again there are two (three Sir!) three things to consider: your current income, your savings or Cash-on-Hand to spend, and the amount of income you will gain (per lot) from a new purchase.
1) If you have NO savings, then the strategy is very simple. If the income gained from the purchase of 1 lot is greater than 10% of your current income, then you should purchase 1 lot as soon as possible. If the gained income is less than 10%, then you should save up to purchase 10 at once.
2) If you have some savings, but less than needed to purchase 5 lots, and the income gained from 1 lot is greater then 10% of you, then you should purchase 5 lots as soon as possible. If you have more than enough save for 5 lots, then wait until you can buy 10.
3) If the income gained from the purchase of 1 new lot is less than 10% of your current income, then you should always save up for a purchase of 10 lots.
4) If you won't be playing again for a "long" period of time, don't be afraid to buy anything you can, because it ALWAYS pays itself off eventually.
If you noticed (in 2) there is a fuzzy line between buying 1 and buying 5, you are correct: There is more to it, and ways to determine exactly what you ought to do and how soon you should do it, but it requires a lot of nasty calculation. The advice above is simple, requires only trivial math, and always works. I'll give those nasty details next time (but not tonight, it's late).