I don't see anything wrong with doing T&M for some jobs. I have a auto shop that just calls and says we need this and this and that and do it, no questions. I charge them by the hr and mark up the parts some, 25% is not bad to me.
To me this is for small projects only. Anything large that requires planning and product ordering is a price job, my way or the highway.
Maybe we should be reporting guys working with no lic where one is required or push to have a lic required in your area if it is not already. This can only help our industry in the future.