Newbie assistance please ...I have most of it down, promise!

[snakepaws]

Ok, I am brand new to collecting (first autograph being Deborah Ann Woll for supporting EJ's eBay "online garage sale" to raise money for charity/research). And now I'm hooked.

Here's what I've gathered so far for my first official dive into this hobby (and please correct me on anything)...
Letter
8x11 and/or 5x7 photo(s)
9x12 photomailer (standard thin cardboard mailer), self-addressed, with (3) USD$0.45 stamps ($1.35)
10x13 white paper envelope to ship everything

Not worried about postage from me to them, as I will pay that in person at the post office by weight. Easy peasy.

Question 1: For within the US (I'm in the US), is having (3) $0.45 / $1.35 stamps sufficient for the 9x12 photomailer with (1) 8x10 photo, or should I make it 4? What if I added an additional 5x7 photo?

I really want to try for Noomi Rapace, sending to her Stockholm address. Same scenario as above with 9x12 photomailer, but with (1) 8x10 and (2) 5x7 photos.

Question 2: How many IRCs would it take for that to make it back to me from Sweden? I've read 2-3 IRCs for international shipping, but would I need more due to photomailer, as opposed to envelope with cardboard insert? And does anyone know the IRC exchange rate for Sweden? I've posted that to the IRC pricelist post as well.

Question 3: As of 5 min ago, the USD-SEK (krona) conversion was 1SEK = USD$0.15 ...that being said, is it common for someone in Sweden to accept USDs as opposed to IRCs? And if so, roughly how many dollars would I want to include to cover postage for the above package? I tried to use the Swedish postal site to get a rough idea about shipping costs, but I'm having very little luck navigating in Swedish. Looks like about 27SEK/$4, but I'm not certain (anyone?). I was thinking of including $5-$10 to cover postage to keep it simple, taking into consideration weight and cost to ship out of the country.

I have 3 US-based mailers on standby, as well as the one to Noomi in Sweden, so any and all help, tips, and clarification would be greatly appreciated! Thanks!

[chamino101]

I can only answer #1: I use 4 Forever stamps on the same white photomailers. You never know what they will add in. I had a response recently that included a couple of pages of handwritten notes and an extra photo.

[snakepaws]

Thanks so much for that! This is actually exactly what I was looking for, someone that uses these mailers and is familiar with everything. I had tried to do a by-weight calculation on USPS, and I kept coming to around $1.90 (being that it would fit the "too rigid" category) - with 4 stamps being $1.80, it felt a bit "iffy" to me. But I also feel I overshot the weight a bit (or a lot), just in case.

So, 4 stamps it is. Thanks again!

EDIT:
Thanks to some help from AzkabanPrisoner...
2: IRCs redeem for 12kr in Sweden. So 2 IRCs would be 24kr, which is enough for up to 100 gram letters (12kr up to 20 grams). Not bad, considering that's roughly $4, and 2 IRCs would cost $4.40.
3: USDs wouldn't guarantee delivery of course, as the exchange rate is high - but someone may just keep the dollars and purchase postage with their own money.

Thanks so much for clearing things up everyone! If anyone else has any input or anything else to add, please don't hesitate!

EDIT 2.0:
IRCs are $2.10 - but $2.20 if ordered online (not sure why). Also, additional kroner is needed for postage OUTSIDE of Europe - not much, but something to consider. If you use USPS website to order supplies (stamps, IRCs, mailers, etc), be sure to expect lengthy "order processing" messages before anything actually ships.