conservative estimate

• cautiousCareful to avoid risk
• lowballDeliberately understate cost
• underestimateJudge too low
• prudentExercising sound judgment
• roughUneven in surface

ballpark · modest · safe · minimum · guesswork · projection · forecast · calculation · baseline · tentative · approximate · reasonable · restrained · careful · preliminary · floor · hedging · assumption

• estimatesestimate, estimation, ballpark, ballpark estimate, rough estimate
• Playing it safecaution, prudence, baby steps, waiting, hesitation