This is my story for your reference. Last year I finished second in the league and I spent $0 in scouting, hoping that I can get a usable player by pure luck. I turn out get an allstar who I play in cup this year and 2 rubbish. Considering that I haven't spent a penny, this drat result is acceptable. This season, I'm undefeated right now and I'm sure I can promote in the next season. With the 16th pick, my expectation is low. I only scout 2 players last week coz I want to try the new draft system (but the 2 players I randomly choose to scout are bad ><)
I do think saving money is important. Coz if you promote, u'll need to buy 1 to 2 already decent player so as to aviod being an "elevator". Also you need to expand your arena which also cost quite an amount of money. (I personally don't like the idea of selling all the players and then buy a whole new bunch of players)
But you may consider a few factors before deciding scouting or not and how much to invest. For example, are the other managers in your league keen on scouting? If no, you may still have a good chance to draft a good player at 16th pick. Also you need to think do you plan to train next season. That is, do you want to train your trainee or just sell him to make money. Personally I would not think my draftees are money-maker tools because the transfer price of draftees varies a lot even if they have similar potentials and skills. You'll need to take a risk. And I also think that the quality of draftees is decreasing in recent seasons.