I would not buy any PSR series or ANY keyboard with built in speakers . On the used market they have no value and almost no value on trade in .
For that kind of money you buy a real synthesizer on the used market . It will have all the familiar sounds like piano and strings as well as purely electronic sounds for when your experience starts to grow .
Check out things like the ROLAND XP-30 , XP-60 , JV-30 , JV-80 . Korg N series synthesizers , or Yamaha S series synthesizers .