in my opinion , "ragnarok hosting services" is a scam ? (OFC IT'S ONLY MY OPINION)
why don't you try to buy a normal vps with the system/ip/protection/specs you want and install rAthena in it using https://github.com/rathena/rathena/wiki ?
it would take some work , but again (in my opinion) if you can't setup a server from 0 , don't open one , or look for a partner that can do it
in the future you will find bugs/problems in the server , you can't fix it if you don't know the basic
just use google and search for a vps with low ping , low price ,1gig ram or more if you want , 10gig storage or more if you want , 1core or more if you want
i would suggest Debian 9 2gig ram 2core