Sunrise, exactly what Vix has said I would do, buy them from the get go because you also might find yourself strapped for cash at a later stage.
I must admit that because this is my "first" (and last) I got myself nice camp cots for the babies, and they will sleep in them until they move to big beds, and if you have big enough space in car, in case you and dh want to go away, you can also pack them with, but yes, there are ways of just making easy beds for them. But I would def buy them before. Also, my mil kept asking me if it was necessary to have all the stuff ready because they were still going to be in NICU for some time and I can do it then, let me tell you, make sur you have done it all before. There was no ways I was going to go shopping for stuff while my babies were in hospital, and then I landed up being in hospital and babies went home before me. Also Im fussy, I like to do things my own way.
Where are you situated?
As for the prams, we bought a nice pram, but now I am sorry we did, Im actually thinking of selling it, its a bit big for us, so shop around and make sure you get what you want and what is most practical for you. (Its easier to go out with twins than it is triplets)
Elamsmom, dh and I had sex 3 times in 1 night!!!! LOL, just kidding, we did IVF, both had complications.