We could argue about whether or not a player is “Scherzer level”, but certainly renting Manny Machado in 2018 cost nothing, unless you’re a big fan of Dean Kramer. Machado was certainly an elite player, although not a pitcher.
In 2015, the cost of renting David Price did involve a highly ranked Daniel Norris. Whether or not you think Price’s significantly younger age at the time was a factor is debatable. Obviously extending 30 year old Price felt like a smarter move than extending 37yo Scherzer will be, but I don’t know if Toronto ever even considered it a possibility or just viewed him as a straight up rental…