Hi Me3,
The only thing I would say is that if something is too good to be true, then it usually is, even the advertised price is very cheap for a 3D printer.
3D printing can be alot of fun, but it can also be very frustrating, I help run two Lulzbot TAZ 5s at work and I have a TAZ 5 & mini at home, after many hundreds of accumulated hours, I can tell you that nothing is set in stone with 3D printing, like most things, problems crop up and can be very frustrating to repair.
In the beginning I was also tempted to get a cheap 3D printer, but after much research, I decided to go with a more expensive Lulzbot mini, (which was a bit of a bargain second hand off eBay) it has been very reliable and mostly trouble free, churning out print after print, but in the end, it is your money.
Best of luck with whatever you decide to do.
In answer to your question, you can draw in sketchup, which then has to be outputted as an STL, which is then processed by a slicing program and converted into Gcode, (machine language) for the printer to follow.
Alex