Everybody always goes for the dark blues in Monopoly (Mayfair and Park Lane in the UK edition), but I'm convinced that the cheaper colour groups offer a better return on investment, partly because you can fully develop them quicker, and partly because you can own more squares, thereby giving you more "hits" and a steadier income. But is there any analysis to support (or refute) this view?
My understanding is that the best three property groups are light blue (Angel Islington, Euston Road, Pentonville Road), orange (Bow Street, Marlborough Street, Vine Street), and dark blue (Park Lane, Mayfair). Light blue is good because the buildings are very cheap but give excellent returns. Orange is good because the likelihood of landing there is substantially higher, due to forced starting from Jail (gets you on a 6, 8 or 9). Finally, the dark blues are a good choice because eventually someone will draw the
There is a much more detailed analysis here. The names are from the American set, but the calculations are the same.
There are two main features in the calculation. The first is to compare the sum of the (hotel) rents with the cost of building. Since the second "set" in each row charges higher rents without higher building costs, we will compare only the four second sets. The rents appear first, then the costs:
On this measures, the "light blues" are the most remunerative investment.
The other thing to note is that because of the "Go to Jail" square, one half of the board is much more "traveled" than the other. (Specifically the second and third rows.) This consideration seems to tip the balance in favor of the "orange" properties.