ROI question

[Chance Robbins]

New to the forum so unsure If this is in the correct place...I am looking to buy a property to flip. My basic question is what percent return should I offer my investor and is the % based on the net profit of the property or is it based on the amount loaned? I was going to offer 12% return on the profit of the entire deal...does this sound fair? Or should his return be based on his total investment? Any help with this would be great....I can provide more info if need be.

Thanks