@David Faulkner Your Question of: "what signs do you look for and how do you personally go about telling when each phase transition will start and end, and therefore that it is time to switch up your strategy?"
I make a few basic assumptions:
1) Real Estate Markets tend to be local
2) Real Estate WILL go down eventually and come back up
3) Basic Demographics play a huge roll
I look at how many people are in the pool of possible buyers (age group, income, family formation, investors, hedge funds etc) and the trends as to where people are moving. I look at foreign money coming in. For instance, Chinese money drove up the prices in Vancouver Canada and that bubble will be bursting shortly. When Canada imposed a 15% surcharge on unoccupied properties, that drove the investment money to Seattle which now is also crazy high, and the money went to San Francisco and Los Angeles. Since I invest in Phoenix I expect some of that money to drive prices higher there.
I look at monetary policy and how it affects interest rates. The higher the rates, the fewer can afford to buy. That increases the renter pool and decreases the buyer pool. I look at the offset of housing starts which means the more houses being built, the more jobs and more people can afford houses. Housing permits are a leading indicator that I use to gauge how many houses will be built in the next year or so.
I look at flood zones, earthquakes and natural catastrophes (New Orleans is a risky place to invest because of hurricanes and flooding. One third of the people from New Orleans relocated to Houston and never went back to New Orleans.) It was a good time to own property in Houston and a poor time to own property in New Orleans.
Of course I look at local politics. I used to buy a lot in Seattle but now you are required to accept the first applicant or be sued. The city is sending out "shoppers" to ensure compliance. Sounds like a police state. In Washington it is a criminal act to mail to people in distressed properties but they don't define "distressed". If the owner "feels" they may get behind sometime in the future they can sue you up to 6 years later. Figure that one out.
Illinois is on the bring of bankruptcy. That to me means that pensions will fail and people expecting to live off of their pension are in trouble. Then of course there is the L.A. traffic and their crazy high prices. When I read about people who keep properties in California because some day they will be worth more yet for now are negative cash flow (losing money) I shake my head. Some states have HUGE transfer taxes just for the pleasure of selling your property. A lot of people don't take transfer taxes, property taxes and capital gains into their equations. but I do.
So, I look at trends. I look at what others are doing and how much money the are keeping in their pocket everything said and done. I ask "Is this city worth investing in for the next five years?". I assume a seven year real estate cycle. (generally)
When I see laws are changing against investing, I pull out. When I see large layoffs in an area, I pull out. When I see a new manufacturing plant is being built, I buy in.
I put some long term thought into each area I invest in.