labbitpj,
you can request for multiple samples for freezing. First time is around $320 per year, subsequent samples for around $165 per year. They will be stored together, but in different straws.
Please see doctor early cos for example, freezing takes place on Friday, then DH has to clear the soldiers on Monday, abstain from sex/m~~~ on Tuesday, Wednesday & Thursday, then produce his soldiers on Friday morning.
Also, doctor will conduct physical check-up, blood test, semen analysis before he/she make any recommendation to you for IVF or SOIUI. If both you & DH have no major issues, sometimes doctor will prescribe some medicine and advise you to try natural ( when you visit him, and when he's back for holidays).