The modern pushchairs seem much smaller than those of old, and infinitely more complicated!
When I was due to start looking after my now 7 year old DGS, I was in a lovely charity shop when someone brought a Graco pushchair in to donate, saying it had served all her GC well. I asked about it, waited while the store did a safety check, and bought it for £19.99 including full rain covers and a footmuff. It’s the 3-wheel off-road type and brilliant for dog walks, much better than the little swivel wheels on DD’s £800 iCandy buggy! Only thing I’d change is that I need two hands to fold it, so I’d have had to put DGS on the ground if I needed to get through a kissing-gate or over a stile. I just planned walks that avoided such obstacles. It’s also wider than modern buggies so DGS was very comfortable in it until he was four, when really long muddy walks were just too much and he could rest on the way home. It’s still in use when the now one-year-old comes to my house.
And at under £20 I’ve never had to worry about it getting muddy!