Travelling through chart areas

[MrChris]

Hoping experienced long distance boaters can advise. I intend to travel from Gibraltar through the med, Suez, Red Sea, Indian ocean in slow time. What electronic chart system is most economical when moving fairly often from one area to another?
I am tech illiterate and have given up on Opencpn and going to opt for a plotter/sounder combo and standard electronic chart system as idiot proof option (plus a Garmin inreach). The various advantages of each chart provider are second to cost.

[MrChris]

Still struggling with this. Research leads me to choice between Navionics and C-Map. C-Map "appears" to give much bigger area for your bucks - or am I missing something?