Solo wardecs, like most highsec pvp, have been nerfed into oblivion.
You have to put a Raitaru war HQ in space for around 1.5bil (with core and 1 service mod + fuel for the extra timer) just to get started, then pay 100mil for each dec. That’s the easy part.
Hard part is finding wartargets and not wasting the 100mil. Only about 10% of highsec corp/alliances are war eligible. And most have already been wardecced multiple times by the larger ‘hub humping’ blanket wardec corps, making them somewhat experienced at avoidance.
Once the dec is live, how do you hunt wartargets without knowing they are online? No watchlist means you are chasing ghosts. Can be done, but prepare to spend hours jumping around for nothing.
Much easier to join a blanket wardec corp and share costs, defend structures and camp hubs/pipes.
And ofc most wardeccable corp/alliances can bash your Raitaru (if they can be bothered), so your structure is a write-off.