Hi @Gretel1
Airbnb email system really su**s!
We should have a proper In-Box and/or the email should at least be linked/displayed on the message thread...
But currently we don't know if the email was successfully delivered or read by the guest and we have no proof we sent it... Right here on our CC we have people complaining about messages being delivered to wrong recipients...
With all this I would NOT recommend you to send attachments via Airbnb email system...
The best option is to use any cloud storage services and provide the link for your attachments, you can use services like: Dropbox, Google Drive, Microsoft OneDrive, etc...
I use Google Drive...
if you think the link for your attachement is too big you can use a URL shortner, like
http://goo.gl
http://tinyurl.com
http://bitly.com
Luis