I've read plenty of books on the subject and actually found this website reading one!

I am only required to pay the interest every month, which I frequently pay from the same account.As for your first question.

There are tons of threads on this very subject.3) As one of the other posters mentioned it may be difficult already to sell to a fannie or freddie financed buyer.  

If, for example, a good friend of yours owned a property, and he needed $13k to rehab it, you can absolutely lend him the money to rehab the property and structure the terms and repayment however you like (subject to local and federal law of course).

Then I would check the arv of the property and the amount due on the mortgage to see if you are underwater or not .If everything checks out you can do a subject 2 whereby you take over the mortgage payments and go thru escrow.

If you are doing 4 or less, it really is not worth the cost, time, and increased regulation you are subject to.

I am venturing into subject to deals now...putting my systems in place....let's network!

I'd like to talk to you more on the subject of Marketing.

I would say that $1000 for a weekend course is way too much... then again maybe for someone super recommended by other real life active real estate investors and on a specific subject I want to dwell I would spend that or more.

I have been investing, on a small scale ($15K-$50K per year) in real estate for the last 5 years, so I am not green on the subject of real estate.