I have been shaving my head with a generic grade 0 no attachment shaver but I am finally ready to upgrade to a rotary shaver my budget is low is there any reccommendations?

Things I am looking for in order of importance :

Easy to use

Quick (a few minutes for each shave ideally)

compfortable/not painful

close to the skin

longer battery life

I am not sure this is relevant information but I have Dyspraxia and Autism (high functioning) and I was never taught to shave in general but especially my head so I am going into this hoping youtube videos will help show me how to use it correctly and clean it :)

I live in the UK I am 30 and my budget is about £100 all in thanks guys!