Hey there!

Lots of nonprofits use QuickBooks Online for accounting, but accounting is not fundraising.  There are work arounds to make it do the job, but they are work arounds.  When I made the switch from desktop to online, the Intuit team was really clear with me.  They stressed that the online product was built from the ground up as a new package.  It doesn't have exactly the same features as desktop.  So, if a company is using important features in the desktop product that aren't online, that company should wait.  Personally, I won't go back to nonprofit for desktops.  I love the increased data security, unlimited users, Treasurer accessibility and access to apps like Bill.com and Plooto.

What I do about donor letters is use a fundraising package, like Sumac.  It has a free version for smaller nonprofits:  https://sumac.com/purchase/ 

But if you really want to keep everything in QuickBooks, Gregg Bossen did a session on it at QB Connect this year.  You can find his slides in this very community!  https://qbcommunity.com/t5/QuickBooks-Connect/A-deep-dive-into-Contributions-Grant-Tracking-amp-Dono...

Gregg is a CPA who does a lot of work with nonprofits.  You can find him here:  http://greggbossen.com/

Happy New Year!  If you have any other nonprofit questions, feel free to message me directly.