After pouring a ton of money in these properties, looking at the numbers, it doesn't make sense for these investors to spend any more resources on them.

What resources would you recommend?

But I’ve been trying to get my hands on as many books as possible, as many resources, podcasts, etc., but I was just wondering from my Bigger Pockets family if there is anything SPECIFICALLY that has helped you take large steps towards the direction you want to go with REI and your own personal careers?

There's not a lot of QB tutorials that are specific to real estate industry but a good RE bookkeeper/accountant should be able to guide you to the right direction. 

I love investing and I would want to guide someone on the way to their well deserved rental or flipping properties.

Don’t forget to explore the rest of the sites (guides, blogs, calculators, forums, books, etc).

She will be a great resource to you.

In addition to spreadsheets, I was curious if anyone uses a checklist when analyzing properties; a series of questions, reminders, and information to acquire as a guide you use? 

There are so many great free educational resources online on the details of flipping (and saving on taxes), and even more on straightforward rentals.

Please click on the links, give them a read, and share your thoughts in the comments.First is a post that I feel will help not get overwhelmed with the amount of info that is here on BP:https://www.biggerpockets.com/blogs/5868/52761-the-simple-guide-to-getting-started-on-bpThe second is a post that will help get you focused with your real estate investing goals:https://www.biggerpockets.com/blogs/5868/52743-im-new-to-bp-any-advice-would-be-appriciatedThe last one is a post that will help you choose an “investor friendly” real estate agent.