If you're like me and picked up the lyre (or wanted to) because of a certain Tone-Deaf Bard, here's some things I've learned:
A beginner lyre is likely going to have cheap or worn-out strings, so I recommend changing out the strings. Replacing my strings has helped my instrument stay in tune, and I rarely have to make huge adjustments anymore.
String oil has also helped my lyre strings last longer and stay in tune. It also makes the sound a bit warmer (a little oil goes a long way)
New strings take a couple of tunings before they're fully stretched out
Bridge placement can drastically affect how easy your instrument is to tune, especially from A5 onward -- shorter strings are easier to tune to higher notes. Too much tension on longer strings will cause them to snap
Right-handed and left-handed lyres differ in string orientation. Which you choose is entirely based on whether you like the low notes closest to your body as you play, or the high notes closest to you.
There's no need to buy a special tuner if you have a smartphone. The "daTuner" app has my favorite chromatic tuner and it's completely free
The lyre is the easiest instrument I've ever picked up. It's very beginner friendly, and there's lots of free tabs out there if you're not comfortable reading sheet music :)
My two favorite YouTube Lyre creators are Samantha On Mars and Learning the Lyre Harp
Samantha On Mars posts a lot of Lyre tabs, and Learning the Lyre Harp is a channel that's helpful for deeper music theory concepts. They're both lovely, and Sharon (learning channel) has a weekly online meet-up through her patreon if you have questions.