Simply avoid!
I contacted Trackmyhashtag for help with a historic Twitter search and provided the date range across which I would need them to collect all Tweets with a specific hashtag. Their initial cost estimate was astronomic, though after some back and forth they cut it down. I submitted payment, and then (after they already had my money), their representative contacted me again to say that their estimate was off and informed me that they were now demanding a new price that was nearly 3 times what I had already paid. I tried asking for a new cost estimate with an abbreviated date range so that I wouldn't have to pay any additional money, yet they refused to do so, so the only solution available for me to receive any data for the money I had already sent them was for me to send another payment... While I eventually received my data after this second deposit, the entire experience was scam-like. No reputable business keeps a customer's money and product hostage while demanding payment far in excess of initial estimates.
