The reality of real estate investing is that you only need two tools.  1- a Blue Pen2- a Note Pad.  

I've built a tool for myself that I use for my own applicants where they can only retrieve data from their bank, HR system, govt sources for background check, etc.

DSCR becomes a scaling tool when you stop treating it like a shortcut and start treating it like a discipline.A few things that have mattered most for us:1.

Hey Jihea, there's already a few tools on the market place that do this. 

How would a computer program/ app/ AI/ google possibly know the correct price for specific work completed or even materials?

Do I need a broker or can I use BP Tools to address the background check and lease?

It also has a bunch of really unique benefits/tools for your rental portfolio (Lease Indication Tool, Expense Tracking, Maintenance Requests, Rent Collection, Tenant Communication, etc.) in one central place.

Has anyone used the DIY tool, and are there risks?

If it is customized correctly, QBO Plus or Advanced can be a very powerful tool in managing the financials of your portfolio. 

Your best bet is to pursue DIY landlords, but your biggest challenge with them will be getting them to pay for services.Just look at many of the posts here on BP where these owners are always searching for FREE tools and complaining about anything they have to pay extra for.