Wjen I try this I buy the card put it up and then here come all these lower offers. I leave it there, 3 days later there are still tons of lower offers, do I have to lower my price and break even or gain a much smaller profit. You are ignoring the research part, you have to know if that price is higher than normal right now. It's just too much for me to deal with, it's not like souvineers back on 18, never have I ever seen an easier method of making stubs than exchanges for souvenirs.
But yes there is stubs to be made flipping if you know where to look.