Strategy tips when you are absolutely forced to play by that house rule:
Buy every property you land on with the possible exception of the Pacific-North Carolina-Pennsylvania trio.
Trade like hell to get yourself the St. James-Tennessee-New York trio, if that's possible.
Whatever monopoly you do get, develop up to three houses ASAP.
Freely mortgage whatever properties you aren't developing, with the possible exception of railroads.
Reasons:
A. Pacific thru Pennsylvania is a great trio in theory but it's also the most expensive set of properties to develop. More people bankrupt themselves trying to build them up than bankrupt others by playing them.
B. Between getting out of jail and the "Advance to New York Avenue" card, that orange trio is the most landed-on monopoly in the game. Most people overlook that fact while trading properties.
C. There's a disproportionate leap in rents from 2 houses to 3 houses.
D. You will not win the game by collecting 12 bucks' rent from Virginia Avenue. If that monopoly is blocked you're better off mortgaging it for $80, coughing up another $20 cash, and putting another house on New York Avenue.