would the parts it printed out be strong enough?
Kind of an open question depends on what forces you are talking about compression strength shear strength or tension strength.
People are making prosthetic hands for kids from PLA they get quite the workout.
would that depend on the type of plastic/filament i buy?
yes different materials will give different strength. High strength materials such as nylon will require more heat to process and likely beyond the limits of a low end hot end found on most printers You will need an all metal hot end such as an ED3 this is a $80 upgrade that you would need to install.
Price aside you need to figure out what features you need in a printer.
Things to consider.
print envelope what is the max size part it will make.
power supply amps/watts
Heat bed
Hot end
On board controls
Type of frame jungle gym , wood or metal cube.
Looks is a clean neat appearance important.
Open or closed source. Does the manufacturer require you to purchase there filament , do you need to hack the machine to use open source material.
This is one to look at http://www.plasticscribbler.com/produc … terid-2000
Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura