Financial independence and personal finance in general is also a big interest of mine. I'm lucky that my wife was receptive and is now a valuable partner in the process who is in general supportive of the various steps to get there. We have stayed living simple in what I would describe a "resident plus" lifestyle for the 3.5 years post residency for me (9+ years post dental school for her). We try and spend about 10k a month all in between housing, travel, food etc which is pretty close to 5k per person per month as have have fairly equal levels of spending. There have been additional bumps in the road including our wedding and some car purchases that aren't accounted for in the above budget. On the 10k a month I feel like we live very well, though we have a simple apartment and shift spending from housing over to very non-resident extravagant levels for travel, food, wine and of course savings. Ramit Sethi has a great phrase "spend lavishly on the things you love and cut mercilessly on the things that you don't." My goal is to go at least 5 years post residency on this budget and then start to open up the purse strings a bit more and look into the finances of a nice doctor/forever home. Since we live in CA that is likely to be 1.5MM or more unfortunately.
I have thought long and hard about alternative streams of income and keep coming back to medicine as it is just so much more lucrative than the alternatives. When I can make 200-350 an hour it seems best to just do that, pay the inevitable taxes and then put that money to work with investments which provide their own "alternative stream of income". Up until last year I was mainly limited by how many shifts and hours were available, plus how many I could reasonably fit into a given month while maintaining my sanity. Now I've been able to add in some additional SDG admin time, plus hospital admin positions that are all compensated and can fit time around shifts, plus a bit of telemedicine so I can really work a lot and have essentially doubled my income. I'm working super hard right now, but as you are all aware with the shaky trajectory of EM I am wanting to race to FIRE and then decide on the pro/con of major purchases, especially with recurring expenses like a big house vs how much to work vs pursue fatFIRE dreams down the line. We just hit our leanFIRE number late last year and are well on our way to FIRE goal in 1-2 years so I'm pretty excited about our future financial flexibility just 5 years out of residency and plan to cut back a little at that time to "normal" EM work levels of about 120 hrs a month clinical plus some admin and then coasting along from there, decreasingly clinical time every few years so it always feels easier rather than having to step backwards. I do love my job and my ideal "retirement" would involve some sort of admin plus about 4-6 shift a month, though I bet I would be totally out of the game by mid 50s and moved on to some other encore career after.
Regarding real estate, living in CA the rent/purchase ratios are so out of whack that it doesn't seem like a great idea. I have been researching a number of private equity real estate sponsors and have settled on a few that I'm investing heavily into in order to get some good real estate exposure in my portfolio while letting some experts find some great opportunities. Once you have a trusted sponsor and do a few hours of due diligence for each deal it's pretty much completely hands off. Historical returns have been in the 12-17% range IRR for lots of the deals in the space I'm investing in, so if that continues even at a heavy discount I'll still be very happy and it's replaced my prior bond/cash allocation making up 35-40% of portfolio. My wife is looking to go part time in dentistry in the next few years and we will be looking into getting at least 1-2 in person properties even if they aren't amazing deals if they allow us to claim real estate professional status for her. Through 2022 you can also do accelerated depreciation on real estate which allows extra losses to be passed through against active income, so for the right property the 100-500k depreciation that can be passed through to my income with incredibly high tax rate could provide enough savings to have even a prior poor investment CA property become a reasonable deal.