With a short supply of homes on the market and limited new construction, communities that were once considered unsavory are now becoming desirable investment opportunities.

IF you have a lake close by and a way in you can get ALOT of water underneath,  Second check for leaking pipes under there right now,,,both supply lines and drain lines. 

Find out:Your target area; ALL costs of a mail campaign (list, letters, postcards, necessary office supplies, postage, etc); budget for 6 months-1year of mailings; develop scripts for prospective sellers (what to say to them); learn to track responses, follow-ups, conversion rates, overall campaign effectiveness, etc.Build your team; title company, RE attorney, cash buyers, closing agents, etc.This list may seem long and overwhelming but if you're looking for a "secret sauce" in this business you wont find it.

They seem to have an unlimited time supply and pickyness about seemingly random things. 

Those marketing resources, (in funds and time), make up the volume discounts that the property manager realizes as they pass more work along to the contractor than the vast majority of private citizens, or even a small or medium sized flipper or landlord.Obviously, a large flipper/investor on BP can generate as much or more work than a small or medium sized property management company, which would also translate into more aggressive pricing for them as well.  

@Aleksey Vinogradov - at least in my area, ready-mix companies usually only supply the product... you'll still need a contractor to place the material, unless you're doing it yourself.

I started doing type of aggressive [crazy] goal setting a few years ago and I've been totally amazed on what can happen when you have "out of reach" goals set for yourself...Just my two cents.

No paperwork being supplied is a problem, there are obviously more problems then he is letting on.

I goto a plumbing supply place for hard to find fittings right up the road from there.

Which is if you haven't done too many rehabs probably best to stick with properties where only cosmetic work is required, and once you have a few of those under your belt you can take on more aggressive rehabs.