Hey Jake!
First off, congrats on the successful house hack back in 22! Sounds like you got a winner of a deal there, and all things considered a great interest rate before they shot up in 2022!
I'm a local lender based out of Bucktown and work with a ton of investors, and help host meetups in our office. It sounds like you have a good idea of what you are doing and are looking to speed things up for future purchases.
1. I'd agree with John- anything with blue line access seems to see quite a good amount of price growth year over year. There is some other up and coming areas where we are seeing a ton of activity with house hacker (unsure its somewhere you'd want to live TODAY though).
2. The biggest change in terms of lending programs id say is fannie's changes to allow for 5% down for 2-4 units. That said, like John mentioned above me, if you're looking for more of a value add type deal, than 203k and homestyle offer great assistance!
answer to #4: Speeding things up to do more deals every year, i'd say begin looking into partnering on deals with friends or family who perhaps have yet to purchase a property so they can use an fha 3.5% down or 5% down conventional loan, you gift them a portion of the downpayment for a % of equity in the property. Other options would include tapping into the equity of the current property through a heloc or cash out refi to fund the next purchase, or be able to put 20% down for a straight investment property or using private money. Depending on your liquidity/vesting in these retirement accounts - utilizing these accounts can be a great way to purchase more property, you'll just want to be sure you're covering all the bases to keep you on track for retirement, emergency fund etc.
If you have any more specific questions as it relates to financing i'd be happy to chat more in the DM's!
Best,