I started in my car too! Well... More like basement until the wife kicked me outta there haha!
I had a trailer hitch already from my little boat I pull around so what I did was bought a cheap trailer for $200 +$40 new wood and it works great. I have held up to 1.1k in there and my Sebring pulled it around just fine. Now the trailer is just a little extra room behind the truck, but its still in use. So far I have a truck, trailer, magliner, dewalt set, and tools paid for with scrap. Im also going to start saving for the next truck since I know mine wont last forever =P
My advice would be "stay in the black" and work smart. I have already hurt myself a few times by doing dumb things... not to say jumping around on a car hood to get it shoved in a car is dumb... but I hurt myself doing similar things and then lost out on multiple days of working =/
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