TLDR:  My physical therapist is charging me $400 a month in co-pays AFTER insurance.  Don't feel they're worth that.  What exercises should I do?

53, haven't ridden my bike for a couple of years.  Couple of months ago set up at a gun show and really tweaked my back - like rolling over in my sleep caused me to shout in pain.  Went to PA, got anti-inflammatory, muscle relaxers.  Went to spine doc, actual MD.  Diagnosed arthritis btwn L4 & 5 based on the CT scan, not a huge surprise, have it in my knees & toes from running.  He offered me a steroid shot, which I declined given my history w/ steroids.  He referred me to a local physical therapy place.

Therapist has a doctorate, her assistant is in school.  1st session they evaluated me, & gave me 3 exercises centered on the back & hips.  Been doing those, quit the meds, mowed the lawn yesterday, feeling pretty good.

Today was all core strengthening exercises, some involving equipment that I don't have at home.  I wasn't sold.  Cancelled all the other appointments I had scheduled.  No other home exercises were suggested.  I don't feel doing core exercises twice a week in their facility is worth $100 a week + what they're getting from the insurance company, when I could watch some YouTube videos and do those exercises every day.

What exercises that I can do at home, or YouTube, Rumble, or Playeur channels do you recommend to strengthen my core?  As soon as I replace the tube on the bike, I'll be back on that & running errands on that.

What 3 exercises they give you to do?

Lower Trunk Rotations

Bridge

Hip Abduction

Mine are fused. I was told hanging from a bar and doing the best crunch I could do for as much as I could would help build support.

Any physical limitations to justify that prescription?

As cheesy as it sounds, the Ab Ripper X program does have some good movements and you could build up the volume as you progress, start easy, work your way up, pick the movements that work for you.

Scissor Twist
Row Your Boat (yeah, I said cheesy)
Superman Banana
Oblique Crunch
Roll V Hold
Abrinome
Gate Bridge (it's just a fucking leg raise, but the fitness industry has to make money some how)
Phelon Twist
Scissor Clapper
Tornado
Balance Bike Crunch

Well, arthritis btwn L4 & L5...

I'm still in pain from therapy 2 days later.

That's the sorta thing I'm looking for, thanks.  I'll take a look at it.