In order to do that, I'm seeking a investment mentor who can help me to increase my knowledge, who can help me to develop techniques and strategies, who can share me their experience on wholesale, flipping houses, on landlord, on residential and commercial properties, holding, etc.

I was hoping to get a response from some people who have actually made money using similar direct mail marketing techniques.

I can also give you a few techniques that I use to continuously get a piece of the "Detroit Pie" again and again.

Hopefully you are applying some techniques that may land you some generous returns on rents.If the prices in the market are high I'm pretty sure rents are skyrocketing as well.  

@Brian Gibbons is my favorite expert on this technique. 

Maybe you used this technique starting out, maybe not.  

I have never done this technique and I have only known one guy who does this, so I cant even give you the total mechanics of the deal.

I also plan using wholesaling techniques to acquire more properties or sell the ones that do not fit as a good rental.Ive owned my own home for 15 years and have done major renovations by either myself or as a general contractor.

this is a belly to belly business.. unless you have 100's leads ... its not wise to do anything but make an appointment for a sit... then use your skills and sales techniques whether they are soft sell like Brian or hit you over the head the J Scott... but you would be amazed at the deals you make when they sounded rough on the phone and were completely different in person.I worked for 15 years shagging leads and doing in home presentations... its night and day from phone and in home.. and a really great sales men can turn someone around on a dime. 

So the presentation is about to start and I decide to write notes on his selling techniques( I was really into human behavior at the time especially after watching Lie To Me). so He's going on and on and I note how he's making the crowd comfortable and making them like him with his sense of humor and such (I later Found it's called "building rapport") and I also notice on how he plays on some of the older's crowds sense of regret of not working harder when they were younger to build a better life.