Not affiliated with either company** 

It really is a minefield out there.I know everyone likes the convenience of the web, and they are tired of hearing it, but this really is a business based on relationships, not online anonymity.

This tool (no affiliation with BiggerPockets) can help your son find properties with assumable loans. 

Most of the large lenders have affiliate programs and will teach you for free to represent them.

I have a 6-figure land business & am just here to help (no affiliate links).The best land investing program I have seen is Jonathon Haveles with The Land Method and Land Riches Blueprint. 

Note I have no affiliation with him.

I never used it and not affiliated with Michael Blank.http://www.themichaelblank.com/syndicated-deal-analyzer/

Find one with flexible pricing options, no long term monthly commitments and affiliate referral program.

They are very up front about the whole process and all the details.Before I go on, I want to make it clear that I am a small time entrepreneur and am in no way affiliated with the Capital Syndicate, Awesome REI or anyone else associated with this course.I bought the Capital Syndicate course because I wanted to see if I could apply it to a specific niche market.I bought all the add ons because I wanted to make sure I gave it every shot to work properly and because they offered a 30 day money back guarantee. 

I scoured craigslist, the web and facebook for people to do very specific tasks.