I would say the costs for sharpening equipment depends on what someone consider as a '' well maintained edge''.Yep, very true but I also find it strange that there are so many knife enthusiasts who spend an absolute fortune on great knives and then only set aside a few peanuts to keep those edges (the most important part of a knife) well maintained.
If well maintained edge for lets say a freehand sharpener is highly polished and refined edge and this person thinks that only the best and most expensive bench stones up to #12000 can do such edge and he also wants to add all sorts of lapping films and exotic diamond pastes up to 0.01 microns to the sharpening process….well….it will cost a lots of money at least for my standards.
The same goes for a person who thinks only Grid Viva sharpening system with three decimal accurate angle cube and a set of best Poltava (or whatever highly expensive) stones out there can sharpen the edge on his knives.
But there is a guy who can get a sharp edge on all his knives only with DMT coarse (or DMT fine) and 3 micron strop. So; one diamond plate and a strop for well maintained edge. Compare to those two examples before this is indeed peanuts money but the result (maintained edge) is achieved.
I can also give as example other guy who can get hair whittling edge only with DMT coarse/fine folding diamond sharpener. The same guy can get a scary sharp edge on his kitchen knife only with Norton Crystolon 120 and a strop with brown compound.
Someone with no retentions can get a good guided sharpening system with a set of diamond stones out there for small amount of money. Add to that a strop and not expensive diamond compound and you can put a good edge on your knife.
What am I trying to say; you don't have to invest a lot of money to keep your knife edges well maintained.