I built a 4' X 16' pit in my garage, I love it! No more creeper under the not enough room places, and never have to struggle with underfloor stuff. My exhaust work is now a snap. A lift would be good too, but I don't have a post (or 2 or 4) to work around. My total cost for the pit was less than $1,000.00 including 2" x 6" decking to cover it when not in use. Definitely do something to get under your car easily, you will be glad you did. Don't forget to put an electric plug in the pit too, I did and now need an extension cord to get my power in there. Also a drain if there is possibility of getting liquid in there, slope the concrete away from every edge of it too.
