It depends on the thickness and amount of trees.
10 trees up to leg thick I would simply cut with a new bow saw.
For 10 larger trees, a bit less or more, I would hire somebody to fell and section it. The rest I would do myself.
If you have more trees and a fireplace and think that you will also in future make firewood, perhaps in foreign woods with permission, you should make a chain saw course and buy a quality saw.
You need to look where in your area is located a chain saw service point. You buy in the service point that is located next to you and that sells Dolmar, Stihl or Husquarna.
For you it doesn't matter which of the three brands you buy. For you is important that the service point isn't far away.
The quality of them is relatively equal.
Dont buy an electric one, buy a light fuel motor saw!
Don't mix yourself, buy the ready mixed fuel in the service point!
Afterwards you drive the tank empty and then detension the chain.
Cable saws are just for cutting wood next to your shed. High quality akku saws are expensive and mainly sensible for tree climbers and people who saw professionally in towns, also early in the morning.
You need to invest approximately 500 € into the saw. Don't take a 250 € version, they are no good quality and you can't work with them longer than half an hour.
You need something that's made for farmers. No hobby class, no forester class, but farmer class in between.
And you need special protection boots, trousers, helmet with eye and ear protection. Leather gloves too.
if we just talk about felling and sectioning a few trees it is surely cheaper and easier and also less dangerous for you to hire a specialist.
I did fell a few trees. I got payed for a few. I got payed for a few that I climbed up and cut them meter by meter with the chain saw down while I was hanging in the tree.
I helped a few moth a specialist who did that professionally since many years.
And I recently found someone who is willing to come next winter to our farm here and take away the 20 metres high 200 poplar hedge for free.
He gets the wood, we get rid of the problem.
He comes with a harvester, I will stay out of danger.
Tree felling is DANGEROUS.
I avoid unnecessary risks.
Some trees are protected, for others you need to ask official permission, hedge and tree cutting has legal seasons regarding bird protection.
A specialist also covers that all.
And if you want, he takes all the branches with him. That costs of course but just look how many branches are at your trees and imagine to have them for a decade in a corner of your garden.
I recommend to fell trees before you plant or build anything.
Felling with just 3 cuts and sectioning on the ground is far cheaper than tree climbing.
Depending on the area and situation felling and sectioning a tree like it's done in the woods may cost 100 € while a tree climber will ask for 300 to 500 € for the same tree.
There aren't so many people who are willing to hang in a tree and to cut there with a motor chain saw approximately in the height of their own neck.
The few who are doing it ask for a sensible amount of money of course.
That's the reason why it's pretty idiotic to let them grow too high in a small garden.