I can only answer for the Houston location, but I asked them many of the same questions when I was there on my tour of the facility...
The fleet is newer Archers and Seminoles, all were Glass except for one of each. They have a full time A&P on staff that handles all work for the school.
They have visits by recruiters every 3 or 4 weeks. The visiting airlines done follow any kind of schedule, so it is hard to say how often Envoy would be there.
The Chief Instructor was upfront about the fact that you will more than likely spend more than you expected. Many need more hours than planned for prep prior to a check ride. Also check ride costs are not included in what you pay to ATP, so this alone will be several thousand dollars.
The ATP financing is with the two companies listed on their website. They seemed to push quite hard for me to apply for financing while I was there, so I assume there is some form of kickback to ATP as a referral fee. They did tell me that if going with an outside financing method the payments to ATP can be spread out and will not need to be paid up front.
Timeline for smaller schools like Houston can often be as advertised due to the lower utilization of the aircraft and instructors meaning more availability to fly, however weather delays are always possible. For staying as a CFI to reach 1500 it can be a little weird. You will not necessarily be able to instruct at the facility you want to be at. They will give you a list of locations requiring CFI's and let you pick. Also, note that some of the smaller locations may not have you flying as much as you might like. At Houston each instructor currently only has 2 students. This also affects your pay as you get a higher rate for flying more hours.
Tuition reimbursement is paid directly to your account if using their finance. It is paid to you if using outside finance.
Housing at Houston was 200 per week for duel occupancy, although I was told that often you have the apartments without a room-mate. I didnt look into this too much as I have a family and would not be using it.
They were pretty open with ipad requirements. They all appeared to use mini's at Houston. A foreflight subscription is required (paid by the student)
Cross-country is arranged by ATP. You call in the morning and will receive your route for the day. ATP will arrange all hotels etc.
Yes tours are possible, I included contact details in the other thread.
This info is current for Houston within the last few weeks.