I haven't seen a lot of discussion about this topic which surprises me since I feel like personal finance people talk about HSAs all the time! 

thanks.Ask and answered already here https://www.biggerpockets.com/forums/51/topics/1223534-boi-r... 

There's a specific forum for House Hacking.You'll want to spend some time reading through there as it's a common topic.

Circling back on this topic, curious on others' strategies who are having success on Booking.com concerning how you're handling payments.

Explain your situation and see if there are payment plans or hardship programs available.The BiggerPockets forums have threads on tax liens and foreclosure prevention: https://www.biggerpockets.com/forums/41/topics/766025-surplus-funds-unpaid-taxes-in-foreclosure-saleAn experienced real estate attorney can advise you on your legal rights and explore potential solutions.Have you spoken with your local tax authority yet?

Again, the BiggerPockets store has some books on this topic, or you can learn about it by watching podcasts, reading blogs, and interacting on the forum.

I think I will use this question as the topic for my next youtube video. 

Here are some great resources for you to check out: The Book on Estimating Rehab Costs https://www.biggerpockets.com/forums/12/topics/862964-wholes...Wholesaling Calculatorhttps://www.biggerpockets.com/blog/rookie-241?

However, you forgot/didn't mention the Costa del Sol, which, from an international real estate point of view (the topic here), is what matters.

Again, the BiggerPockets store has some books on this topic, or you can learn about it by watching podcasts, reading blogs, and interacting on the forum.