Realtor Etiquette when there's no deal for a while...

[Rachel Fazio]

Hi all, quick question - 

If you have a realtor you're working with and for whatever reason you end up not doing a deal with them (at least not for the immediate future), but you really appreciate their time and effort, is it appropriate to do something to show it? I have no idea what is appropriate etiquette for this situation or even what the legal parameters are. I know in my field I'm not allowed to take gifts in most situations, so I'm curious what I could potentially do in this situation. Thanks!