This goes back to aggressive PM. I saw a sign recently on one of the FB groups that said something like "if you don't schedule maintenance on your equipment, it will" Anyway, I'm as guilty as most folks about overlooking things but I'm trying to be better about replacing hoses before they break. As suggested by GPAW it wouldn't be a bad idea to replace moving hoses annually on a higher volume car wash. If It will cost you less than a single day's profit and keep things running smoothly it's worth it.
I have the parker mini crimper air-powered crimper. I got it from a local carwash guy getting out of the business along with a complete set of dies from 1/4-1" for $500. Saves me a good bit of time. He said he bought 10K worth of hoses and fittings from a local parker dealer and they included it in the deal. I've had no problem using it with gates or goodyear hose that I buy from KR or CWSS.
The screw on hose fittings work fine for me and hold up longer than the hose will. I keep them on the truck in 3/8" and 1/2". They get a little more difficult to use at 3/4" and 1" but if you keep a pair of those in each size and a length of some hose it can get you out of a pinch and probably still cheaper than local hose shops.
For years I just bought plenty of spare hoses with fittings installed from
Kleen Rite to keep on hand. If I kept a 3,4,5,6 and 7 ft hose along with a couple of now working fxf swivels I could cobble something together that would work in almost any situation. Sometimes I had to loop the extra length but it got me running. I also have a couple of very common ones on the automatic that break so I keep those pre-made.