When I look at tasks, I look at the time involved and the difficulty level of the task at hand. Gutter cleaning is something I won't do myself -- I have a big two-story house with a steep roof and there is no way I would do that myself. I will pay $100 to have someone else do it for me. It is hard and potentially risky work and I would as soon have someone else do that task.
When it comes to lawn though, I've mowed lawns ever since I was 9 or 10 years old (1980) so they aren't a big deal. There are other benefits of doing it yourself as well. Even with a self-propelled mower, you get a decent amount of walking in while mowing and it is nice to get outside for a change. Plus, no one does it as well as I do IMO. I also do my own lawn treatments as well and mowing gives me a good overview of the lawn and what needs done to it -- fertilizer, weed treatment, etc. I've also got roughly 10 flower beds and have to clean and mulch those every year (my wife handles the plants and watering them for the most part).
Don't get me wrong -- mowing is enjoyable the first couple of times per year but then it gets tedious and inconvenient. Even still, I prefer to do it myself if possible. Now, to be clear, there are times when I HAVE paid to get it mowed. For example, I used to go on a yearly business trip in early April and would pay a neighbor kid $30 to do it while I was gone. If the thermometer hits 100, I will probably pay a kid to do it, but even that isn't guaranteed.