Trying to time any market is a fool's errand. It assumes you're smarter than others, have secret knowledge/special insight that most others don't that somehow allows you to predict the future. On average people are...average, which is another way of saying they have no idea what the future holds. Including you, OP.
That said, many of the axioms of buy and hold passive investing don't apply to RE. Unless you're buying a REIT fund, your RE holdings are invested in a specific local market, neighborhood, and individual property. Styles come and go, structures depreciate... many many factors make each home a unique investment.
Buying RE is more similar to picking an individual stock than investing in the total stock market. So instead of trying to time the market (predict the future) think in terms of value investing. Do your homework. Price to rent and price to income ratios for the area, expected cash flow, ROI, etc.
Plan on holding each property for 10 years or longer. Each is a long-term investment. If you're not comfortable with the length of time your capital may be tied up in a property then you have no business buying it.
There's nothing magical about RE. Be principled in your investments and only pull the trigger if the hard numbers indicate a good value. This may mean sitting on the sideline while others are bragging about how much their RE has appreciated, and it may mean buying when everyone is negative on RE (like the last recession). This isn't timing the market, not being contrarian, it's simply buying property when it's a good value.
Never, EVER, count on capital appreciation to make the math work - this is the fast track to losing money with RE. An investment property has to be justified solely based on the strength of the income it generates. If you get some capital appreciation along the way then it's icing on the cake.
About that piece of shit fixer upper: Do you have a realistic understanding of how much it will cost to fix it up? I cannot overemphasis how much of a bottomless pit RE can be. One POS property may have mostly cosmetic issues, whereas another will drive you into bankruptcy (e.g. if you need to hire a civil engineer to stabilize the property, or replace the foundation, and so on). If you've not factored actual estimated fix up costs into your calculations then I'd bet dollars to donuts that you're banking on future capital appreciation to bail you out. <-- Don't do this! It works out sometimes, but know of lots of people who lost large amounts this way.
Finally, don't be "HOUSE HUNGRY." Instead, be hungry for sound long term investments :)
