Some very inventive people have done cool stuff on youtube. Just a suggestion to check there if you haven't yet.

If I may be so bold - what is your idea of a finished project going to be, do, accomplish?
Is it a toy to just ride up and down the street in front of your house?
Is it going to take you to work? or replace other transportation?
Is it going to save you something? Time? Money? Stress?

If you don't have answers to these ??'s then before you spend anything - figure out what you are spending towards.

Since you say money is tight - spend it right.

Hope it helps.