A successful BRRRR without the tailwind of market appreciation during the renovation period is really, really hard unless you have cash to buy a place that does not qualify for conventional financing, ways to source off market deals with some real issues that you don't mind taking on, and/or access to a crew or cheap labor (could be DIY).

I only use Zillow but want to ask is a more comprehensive listing that I can access (for example, which is the preferred source for foreclosure homes). 

Sharing some info from two sources this weekRegarding states looking to strengthen seller financing licensing requirements and court decisions for those not licensed:First from Facebook group school of sharks:Hey guys,TX Dept of Savings and Mortgage Lending has some new rules that are expected to go into effect January 01st, 2025.

I’ve found list source to be low quality for MF at least in Missouri. 

. - For greater than 5+ multi family properties the 'best' initial source for financing could be a local credit union or bank.

-Thinking long term, is this something I could scale to make my primary source of income?

Getting creative about using your primary as a chess piece for your investment journey is just fun and probably the best way to hit the fast forward button on your investment journey (so long as your reserves and marriage are strong enough to handle it).Honestly very smart way to play out using your main property as a source of income.

Is there any source or tool to calculate those expenses?

You are filing jointly, so only one spouse needs to qualify as a real estate professional to offset income from income sources such as your W-2.

Go to the source and I bet you get the answer quickly.