If they are not licensed and bonded (insured) proceed at your own personal risk.
I have had a few door nocks and winter trims done for next to nothing. They all claimed to be bonded (insured).
I had Rainbow Tree trim the Green Ash that runs partly over the top of my house. Rainbow is already doing the chemical treatment on my Green Ash. City I live in helps with a discounted rate on the treatment. The treatment is working … Rainbow tree trim was pricey, but man they did a great professional job.
Best was this late spring. A city crew came down the street and trimmed up all the big trees that had branches hanging over the street. They did a nice job to balance out the project too. Not often you get something without paying extra (can’t say it was free, by property tax statement would prove that).