Flood risk concern

[Junalgen Milan]

Hi! I'm a new member and bought a property in MD with concern on flood risk. On FEMA, it is categorized as X, with 0.2% likely to flood this year. But when checked flood factor, it says flood risk is 9/10. Property has no history of disaster report. is flood factor reliable? Does this means i cant create another unit in the basement? How do you mitigate? Lender dint require for flood insurance. Property has an in-law suite, that's why i bought it but flood factor risk report put me in panic mode.