Even scalping isn't going to guarantee 2% a month, especially if you are new at it.
Suprised no one suggested starting a local post up book. That opens up a lot of options for you. Either booking them yourself, or laying off at a premium through some offshore books.
150k is more than enough to start a post up shop. Granted, most guys don't like to post up, but credit shops are hard, and a couple deadbeats kill your expectations for the most part, especially if you are laying it off.
Also real extate and rentals is no guarantee. Again,a couple dead beats that can't pay theeir rent will catch up with you.
I am doing that now, and trust me the laws, insurance, and technicalities don't make it worth it. Even in Cal where you can get 2500-3000 a month for a decent 3 bedroom in some neighborhoods.
Get an accountant.