What are your thoughts on investing in Los Angeles? Ex project: purchase single family, tear down, and build multiunit.

It seems to me like it would be really expensive to do so, maybe come with the same strategy and look for a house thats 3 beds maybe you can add a divider wall to rent 2 bedrooms make the 3rd a studio and convert garage into ADU might be cheaper than buying tearing down and building

If the zoning is right and the numbers crunch out, why not? But as @Cesar Ruiz mentioned you could look into the ADU route. If it is a multifamily zoned lot you can build two detached ADU's.

It depends on how many units you can get on the property. If you're tearing down SFR for duplex of triplex, its probably not worth it, and you're better off keeping the value of the original home and going the ADU route

I've been evaluating SFR properties for small lot subdivision redevelopment, and 4 units is usually the minimum amount needed to pencil out the development, but lot size and neighborhood are a big factor.