Risk question for newbie

[Chris Ballinger]

I am pretty new here but wanted to get an idea of how safe my margins should be I come across quite a few properties that can make money but unsure if I should pursue because I was told you want at least an 80k spread. 

Ex  purchase price $220k

      Rehab. 20-30

      + closing and carrying

I know when done I could cut the property lose at 275k or hold out for 290k

Is under 10% low side to much of a risk? 

Thank you