Letter of rec etiquette for grant apps?

[videokid]

Hi all,

So, I made it to grad school, so I sort of know the drill about asking for letters of rec, but, now that I'm applying for a few different grants/fellowships this summer (one to fund conference travel, one to fund a week of archival research), I was wondering about the etiquette regarding thanking profs/advisors for letters as a grad student. That is, at this point, it seems like having to ask for letters is going to become more routine, it basically just being a given/part of a prof's job that grad students will ask for letters. This being slightly opposed to the less-given responsibility of writing for undergrads (i.e., not every undergrad is going to go to grad school & so need letters, but every grad student is probably going to be applying for funding throughout their program). So, with my undergrad letter writers, I wrote heartfelt thank you letters/got them a (small) gift, etc., because it felt like a big deal, and that seemed to be one of the rules of asking for grad school letters: "thank your profs, thank them in writing, it's not a huge deal but its still extra work for them, so, be gracious, and not just an email". 

But what about now? Do I need to go for a card? Or are the "thanks"/"thanks so much"'s I've been emailing along with the fellowship info, plus an update when I hear back, enough? (I'm slightly nervous because I hope to eventually ask this person to be my advisor and so I really don't want to come off as rude--but also not as overdoing it--hence the overthinking   )

[fuzzylogician]

Saying "thank you" is sufficient and perfectly fine.* Be respectful and mindful of their time, so give them enough notice and provide them with whatever material they need/ask for to help write you a good letter. If you want to send a card, you could, but you're going to be asking for lots of letters and you don't have to buy anyone a gift or card each time you do. What you could do is update your letter writers about the outcome of things they wrote for once it's all done, and thank them again for their help regardless of whether you were successful or not. 

* That would have also been true as an undergrad, btw. 

[TakeruK]

In addition to what @fuzzylogician said, in many cases, it's in your advisor's own best interests to write these letters because any grant dollars you get reduces how much they would have to pay otherwise. But maybe there is a difference in field here? In my field, for the types of grants you're listing, these applications only require one letter and it's almost always has to be from your advisor. 

[videokid]

Awesome, thanks to you both. That's the way I was leaning--but, in my field, funding just comes from the university, not a specific prof. (I haven't even chosen an advisor, yet), so the person writing for me doesn't really gain anything from it--except, really, my gratitude, & so I wanted to make sure to get that part right, having put one more thing on their plate!