Where were the quotes from? Dealer or local garage? First of all, the pricing seems to be fair. Usually from $89.99-$109.99 for coolant flush and between $129.99-$189.99 for transmission. The thing to look for when you decide is to make sure it is actually a "flush". Some garages will only "drain and fill" but tell you they "flushed" the system. Draining and filling does not replace coolant or transmission fluid in some parts of the system but a pump assisted "flush" does and that's what you want. To me, the price isn't that big of an issue if it's done correctly. An engine oil flush should only be around $10.00 extra on an oil change since there is no labor involved but pouring an engine oil cleaner into the old oil and letting the vehicle idle for 5-8 minutes prior to changing the oil and filter.