capital improvement assessment and 1031 questions

[Lonzo Seebe]

Good evening all, I'm a brand new member!

I am selling a property for $500k that has a $50k special assessment for new windows, doors, etc to be paid over the next 13 months. It is not due yet.  The buyer asked me pay it them roll it in and increase the sales price by the same amount.  

If I do this for them how would my 1031 look?  Could I purchase a property for $500k since that is all I will actually receive or do I have to spend $550k?