Printing Maps To Scale

Kia ora, happy holidays. I guess I'm old school for not having a smart phone or GPS (and even if I did, I'd want back up paper). Anywho, with the LINZ and topomap websites having quite functional online mapping services, it'd be great to take advantage of printing the areas I actually want for tramps rather than buying 3 sheets for $30 because my 2 night tramp happens to cross different sheets. But I'm having some trouble printing from them. While living in the UK for the last few years, I used a mapping service that would allow me to easily divide the depiction of the map into a3 sheets then print those at my chosen scale. It doesn't seem LINZ of topomap offer that. Topomap doesn't appear to print to the scale of the map (just the scale of the projection in browser, which isn't the same as it should be printed - making your 1:50k maps something like 1:47,345 and pretty hard to measure distances accurately with!) LINZ lets you download JPEGs at the correct scale, but you free draw the print area, which requires a lengthy battle with photo editing software and pdf software to only print the sections required. First world problems, I know. Anyway, for those of you who print your maps, what is the procedure you've found that works for you? Is there a service that lets you print chosen sizes at the correct scale? Caltopo offers it for $50usd a year, but I'd rather give my money to an NZ company if I was going to do that.