first build have some questions

[Recon]

so for the motor i think im going to order one from dax's site the 70cc 2 stroke. as for a bike i was thinking a mountain bike but i think a beach cruiser would be fun also. i want this to be a cheap build as im just gonna use this for fun but where do you all pick up these sweet looking bikes? i was thinking maybe the DAV or thrift store?
thanks