Back in Nam in 1970, one of my hooch mates was talking about getting a Harley Davidson motorcycle when he got out. He was going to travel around the country, and the biggest draw for him was that the bike was simple enough that you could "wrench 'em yourself".
I don't know if he ever did it, but I was thinking about that guy when fixing a broken hammer on my Mk VI Webley. Those pistols are simple enough that the only tools you really need is a bunch of screwdrivers and a needle nose pliers. Granted, a spring vise would come in handy, but without one, and range day coming up, you can proceed successfully. It does take a certain mechanical aptitude, but most men have that anyway.
The screwdrivers can be a problem as they are guaranteed not to fit Webley screws. Some have slots that are extremely small, and also extremely wide. My solution was to gather up a large group of old screwdrivers, and with the help of a bench grinder, grind a screwdriver for each screw, a true custom fit. It doesn't impress your fellow shooters to have a lot of rounded screw heads while trying to show off your work.
Mk IV Boer War Model from Adam's Guns
The pistol is simple enough and robust enough to fit the bill of "wrenching it yourself". The problem is parts. Up until about 5 years ago parts weren't that bad to get. Now they've completely dried up. The things you really need are the wear items of the Webley, like hammers, hands and extractors. Some springs come in handy, too. In a pinch, parts from Mk V's and some Mk IV's will interchange with a Mk VI, but they are gone too.
A few years ago a guy from South Africa was parting out a huge supply of Webley pistols on Ebay, before the gun ban. You couldn't get receivers but you could get everything else. I should have bought 'em all and cornered the market. Or at least kept my guns running forever.