As soon as you offered $3500 they knew you were interested and started bumping the price. Unfortunately there is nothing basically illegal about it. If there were other circumstances you could potentially say they are trying to keep you away from the land.
The Texas Real Estate Commission handles all complaints about Real Estate Agents, Borkers, etc. Their WEB site with forms and instructions can be found at http://www.trec.state.tx.us/complaintsconsumer/default.asp.
At $3000/Acre you must not be looking at land in the immediate area around Dallas/Ft. Worth. Land has gone up quite a bit in the last few years. Depending on what you are planning to do with the land, and how close to DFW you want to be, I know of land out my way that has been on the market for quite some time. I'm not an agent or broker but can offer some suggestions. Drop me a line with what you are looking for and the purpose for it and possibly I can point you to some large and small tracts that can be used for just about anything from residential to industrial.
Emmanuel J. Scanlan
PS Inspection & Property Services LLC
TREC License # 7593
International Code Council, Residential Combination Inspector #5247015-R5 (Electrical, Mechanical, Plumbing and Building)
Certified Level I Thermographer (ASNT-TC1A Standards)
Texas Residential Construction Commission, Third Party Warranty Inspector #1593
Texas Residential Construction Commission, Inspector, County Inspection Program
Texas Department Of Insurance, VIP Inspector # 08507061016
Hayman Residential Engineering Services, Field Technician
CMC Energy - Certified Energy Auditor
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