A 300% mark up is rhetoric. My house in a very desireable area, neighborhood, location and lot is about 8 years old. After throwing in what it took to put the landscaping, pool, paint, window treatments etc it was never up much more than double. I’d say that was pretty much the way its been across the board around here. Last time I checked, that was a 100% markup not even close to 300%.
BTW, if my house fell 50% it would be back where I got it in 1998 when things (construction costs, restaurants, movie tickets, gas, health insurance, daycare etc.) were a helluva lot less expensive around here. I just have a real hard time seeing that. If it happens, it would be fine by me as it would allow more nice young families to move into the type of neighborhoods they should be living in.