ETTSI is a scam travel service which works in conjunction with Destinos Unlimited (DU) out of Mexico to sell time shares in Mexico. DU guarantees your first week to be free and your first flight to your time share to be free.
The flight is supposed to be arranged by their travel partner, Executive Travel and Tour Services (ETTSI, out of Daytona Beach, Florida). When you request your flight from your home town to the time share, ETTS tells you they have no tickets for this trip. (I requested air travel from Cincinnati to Puerto Vallarta, Mexico.) I then went online and saw scores of flights from Cincinnati to Puerto Vallarta, but ETTS refused to buy one, prefering instead to keep my money and effectively steal it from me. I encourage you to review (via google) "Executive Travel and Tour Services" and you'll see that every review site give ETTS a one-star rating (out of a possible five) with every review complaining how they were robbed. I requested this flight several times but was told every time that they had no airfare between Cincinnati and Puerto Vallarta.)
Thisi is a scam operation and, if you visit Mexico, I strngly advise you to avoid Destinos Unlimited at all costs.