Does anyone know if Very Solid at D1 is more expensive to overcome than Very Solid at D3? And, if  a player is very solid towards a SIM at D1, but the SIM is far away from that school, and my school is close to him, how much effort would I need to put in to get the prospect to consider me?

1. Sims recruit from the same distance no matter what it states the distance is. It's something like 250 miles.
2. The amount of effort to get someone off of solid would be close to the same as D3 if distance and prestige are fairly equal. The money is much different of course.
3. The amount will differ for different teams so it's hard to say. You might be able to get him for 15k-20k. It could cost much more if the sim has a decent prestige and you don't.

to give an idea, I just put 25K into trying to steal a recruit from a C sim with my D+ umass team and he never budged.  if you have a better prestige, might be worth a shot, but if not, be prepared to go higher than 25K

Yeah - This one is not budging either . I have a D+ and he has a C. I may abandon this plan this time.