1/ Is it worth to spend 90 T-cash for 10 days of services? (I usually buy 9 ores every 2 hours from the dealer)

2/ When the Dealer's 10 days is over, the price to hire him again is 10% discount (81 T-Cash for 10 days). If I don't take the 10% discount, will I receive another chance to hire him for 10% less or even more?