Sims generally recruit for 2 less spots than they have openings, so in D3, if a Sim school has 3 openings, they will spend something like 7-8K on one guy. If they have 4 openings, they will spend about 5K each on two guys, etc.
They do hold some cash back to pursue back-up options after signings start, but they spend most of their money on their primary targets.
They also recruit all players as if they were 250 miles away, so distance is not a factor for them.
So, when recruiting against a Sim, you need to look at how much money they have and how many guys they are recruiting, and estimate how much they put into a recruit. Then look at the prestige difference and your distance to the target.