Flipping a vacant lot - thoughts on best approach?

[Karl James]

So, a few days ago I managed to get a 1/2 acre vacant lot in a very nice subdivision under contract from an out of state owner.  This is my first purchase loosely following techniques like those of @Seth Williams (thanks Seth!) and Rick Dawson (Deed Grabber).   My purchase deal is scheduled to close in a couple weeks and I am contemplating how to best flip the lot.

I am buying it for $13,500 (paying $10k cash to seller + paid seller's back taxes and court costs) to prevent it from going to Constable's tax auction.  I figure I'll have about 6k in it after closing costs.  I had the executed contract in hand before I paid the back taxes and court costs. ($3 to 4k at risk if the seller walk's the deal; guess I'd try to put a lean on the property if I found myself in that position) 

Within the last two months, two lots have sold nearby (same subdivision) for $55k and $57k respectively.  Two more are currently listed at $76k and $79k .  The market is very strong in this SW Houston area (Fort Bend County; i.e. Richmond / Rosenberg / Katy / Sugar Land / Fulshear.) 

I could engage and real estate agent and list it well below the other two lots.  Curious what other approaches have worked well for any BP colleagues, especially anyone whose flipped lots.