I own several prime lenses 28, 50, 85, 135, 200 and 300.
With exception of the 85 all are manual focus lenses. I bring this up due to your comments on budget. The total price for all four manual lenses was about the same prices as one new 85.
Most of what I shot does not require an autofocus or auto aperture lens. For sports with my kids I will use the 85 due to its fast autofocus. The 50 and 135 are 1980's Zeiss lenses and a lot of fun to work with.
These older lenses are metal and glass and stand up well with time. I tend to use them and not worry about damaging them - they are tough.
I keep them in a camera bag and in the trunk of my car if I am out for the day and near the car. If I am on foot, then like others in this thread, I will pick one focal length and work with it. I shoot for fun and I have yet to return from an outing wishing for more than one lens. It can be fun to spend some time with one lens and learn about it.
I also own a bulb blower that is used to occasionally clean my sensor. Part of the joy of digital and lens changing - your sensor may get some dust.
Last January I was in Chicago with my family visiting relatives. We did a trip into the city and I only took the Zeiss 50 1.4. This was a nice size lens to carry. I also enjoy taking a 28 for the day.
This was taken with the 50 manual focus lens on the Chicago trip.
This was taken a few weeks ago at a triatholon my daughter was in. It was taken with the 28 manual focus lens - which is the lens I chose for that event. A small focal length has a more generous depth of field which can make it easier to manual focus for moving objects.