why don't see a lot of people making money from landlording, by buying on mortgage and renting it out?
We do.
if you trust in efficient markets
"Efficient markets" are an idealized abstraction. Putting trust in such seems to be... not wise :-)
Sorry, I meant in the sense some places you see and some places not and this should inform your choice.
Efficient markets is like every hypothesis, it has various probabilities of working in various conditions. Usually we need a fluid market, something that is not like De Beers diamonds, but more like a market with a million homes on a city and hundreds of thousands of speculating homeowners. A market where it is easy to be a vendor and thus collusion and rigging is unlikely. Where the barrier to enter is low. Houses are really close to an ideal market, you...
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