Here is how point buy works in 4e, as a note this is how many points it costs to get that score, for example a 16 would cost 9 points, provided that your starting score was a 10. One of your stats starts at 8 for the calculation, so before you started calculating, you would start with 5 10’s and one 8. There will be two different tables showing this.
|Ability Score (starting at 10)||Cost||Ability Score (starting at 8)||Cost|
We use 32 point buy with this system, so an example of stats you could use are:
This is without racial modifiers or anything, any questions just ask, or try this site out, it calculates it for you, but it often makes mistakes so make sure you check as you go along