On TITO values:
If I need a TITO for my collection I usually will pay up to $1 as that is the least that you need to put in most the slot machines to get the TITO.
For trade stock I generally offer .50 or so. Depending how many dups are in the lot, larger lots with lots of dups may be lower.
As to compare with slot cards, and room keys, 2 or 3 common TITO to 1 common slot card or room key.
As to older more rare TITOs prices have been in ranges up to $5 to $10 in some cases. Yes the TITO field does have some rare issues, think the Reserve in Henderson, NV that became the Fiesta just after it put in TITO slots.
As far as how to mail TITOs I use currency holders, available at coin stores for about .30 ea. Also some people use cut down cor. pieces from used priority mailers.