That would likely be the fastest way to build wealth.

However, I would write down in an excel sheet all of them and process that go into a rehab and do a estimation column and write-down those numbers. 

and it's not that anywhere is "saturated," it's that prices AND rates are high.or as @Travis Timmons said - a creative niche that you excel in will cashflow. 

Just like everyone else, my wife and I am looking to scale our portfolio and found that MF would be the fastest way to do it.

There may be some excellent opportunities there.

That being said, if you’re exploring the BRRRR method, a DSCR loan could be an excellent fit for your goals.

We now have an excellent crew, top notch reviews, and frequent inquiries to join our team.

Personally a cash-out refi could help me get more quickly into all-cash BRRRs or a REI venture in Spain, however I don't know to what extent this is at the expense of rental cash flows, and what is the wiser decision long term.I've combed through posts online and looked for Excel templates to run some calcs and get a sense, but nothing really filled the void... 

Additionally, the area's median home prices and rental rates continue to rise, offering investors excellent opportunities for long-term returns.

I faced a similar problem and ended up creating custom designed Excel spreadsheets that auto-populate with each other.