Agree with dereck. Makeshift or adapted structures are a recipe for disaster.
Personaly, If i were insistent on spending money on home equipment and not joining a gym, I would get a power rack, an adjustable bench, and an olympic bar and weights set. Look on ebay and in local classifieds- plenty of people with good intentions sell this stuff on at a fraction of the new-price. Also search the net for companies that sell reconditioned professional equipment to gyms- they will sell to private persons as well.
For a good power rack, a heavy duty bench, a 7ft olympic bar and 300lbs of weight you would be looking at $800-$1000 brand new, and will probably have to pay $4-600 second hand. Its a lot of cash, but it is the only bit of kit you will ever truly need.
The other option is to join a gym with these facilities and pay a more manageable monthly fee for their use.