I found a CPA to set up an llc and s-corp for me.

Have you considered turn-key/LTR? 

Leverage can help you grow faster—consider DSCR loans or other investor-friendly financing to scale while keeping your workload manageable.

I'm a retired engineer and have been successfully using income from these houses to support my retirement without dipping into retirement savings.I'm transitioning my business from rentals to a franchise and would consider selling one of my houses (5 br/4 ba - the other houses my son while he's still attending).

To adapt, focus on refining your ARV and repair cost estimates, explore off-market deals, and consider creative financing strategies like seller financing or partnerships.

I am considering getting into this space (looking at some courses), but worried that its too late, and that deep local market knowledge/understanding of buyers/connection with developers etc is required to make this work, which only incumbent/long term investors will have and would be hard for a new entrant starting from scratch to catch-up...is my hypothesis valid in your opinion ?

Grind it out for 5-10 years like this and you’ll be set for life.

For that, you'll want to ensure your LLC is already set up and approved in the state where you’re operating.Most lenders are fine with the funds coming from your personal account, especially if the LLC is newly formed.

Considering how rising prices might influence people's decisions is interesting.

Setting up direct bookings is a great way to avoid platform fees!