My two favorite loan options for getting started are the FHA 203k or the Fannie May Home Style. 

And while nothing is foolproof the most consistent method of finding good vendors is relying on OTHER real estate investors that have worked with those vendors.

After sending out thousands and not getting responses, or at least not good ones, I stopped trying this marketing method.

I’ve been utilizing the BRRR method and have been successful thus far.

In addition to reviewing the numbers, take time to tap into your intuition (through meditation or other method) and your gut will help you make the right choice.

It's my preferred method...

My favorite ones (as a Contractor) are those like : "How much will it cost to re-wire my entire house?"....."...

I am coming at this with scientific method trying to find this answer and I can't.     

I think what @Garrett Brown is getting at is using this in addition to other methods.

That trial period lets you see which method works best before scaling up.Moreover, the consistency and success of any agency largely depend on how well you follow up with your project manager and monitor the KPIs.