I have started cutting the hair for both my sons. It stinks but it's less traumatic with me doing it. Less stressful too. I started with the Little Martin hair clippers and now have gone to a Wahl trimmer bc I wanted more lengths bc the Little Martin doesn't do very long. I think 12mm is the longest. They have nail clippers too, I think.

Takes repetition. Nail trimming isn't so bad for my boys now. Autism Speaks has a list of kid friendly hair salons. You can search by state.

My boy is 10, having same issues, nail clipping and hair cutting. So now we cut his nails whilst he's asleep... As for the hair, we trying to figure out if we can cut while he's asleep🤔 that's Kaylan, he loves his curls

Tell them what you are going to do, then sit the clippers by them for a while, then just do it.
Do not share emotions, be factual about it.
Get it done and over as quickly as you can, then clean the area and walk away.

https://www.amazon.com/Little-Martins-Baby-Hair...

These are the ones I use for my son. Best of luck.

Amazon.com: Little Martin's Baby Hair Clipper - Professional Quiet Baby Hair Trimmers - Rechargeable Waterproof Grooming Kit Safety for Baby Toddles Kids (Baby, Blue) : Baby

https://www.amazon.com/Little-Martins-Baby-Hair-Clipper/dp/B075FTR721/ref=asc_df_B075FTR721/?tag=hyprod-20&linkCode=df0&hvadid=693593004876&hvpos=&hvnetw=g&hvrand=14631009339649051400&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=9026822&hvtargid=pla-2207677286052&psc=1&mcid=c449217c0d6f30928a822a8641a46dd1&gad_source=1

Did I mention that I let My Son hold the Trimmer/Cutter before I start?