A 30 amp fuse @ 12 volts = 360 watts
Such a fuse for an inverter may be fairly useless.
You could, in theory, wire several in parallel, but I DO NOT recommend it and it is NOT best practise. (written when I thought it was a 2000 watt inverter).
It is much better to have one fuse that covers the size of wire you are using for the inverter. Carry one or two spares.
If you are selling the RV why are you getting new batteries at all? Use up what you have already. Set up the solar on the ground--and keep it for the next RV.