Welcome to the Forum

I know exactly what you mean about hairdressers. Many years ago I used to go to a very nice young man who always told me that there was no need for perming, setting, blow drying or any products. As long as you had a really good cut.
He was so right.
But try and find one now.

I colour my own hair too.I use L'oreal Natural light blonde. Once a month I go to have a cut and blow dry. AS you say it is flat by the time I get home and I am not expert enough to give myself a good blow dry unless I spent ages doing it.
When I just want to tidy it up, I use my straighteners.

No excuse really. I am retired and have plenty of time.

Hope you find someone soon.