Those aren't difficult to do. However, if I were your contractor, I would weigh the option of doing your job vs. the 500 other jobs I could be completing and charge you accordingly.
Example... In Saskatoon where things are still going full steam ahead, I had to pay $1,100 to install a roofline ridge vent.. materials cost ~ $85. It took about 3 hours, maybe a bit less. But that same 3 hours could have shingled half a house so I was charged accordingly. It can be tough to get qualified people to come do very small jobs. Try and find a good handiman to get it done for less.