Reed didn’t, at least at first. When the Fantastic Four first moved into the Baxter Building, he rented the top five floors, a situation that persisted for years–past a certain point the FF had recurring difficulties with their landlord, Mr Collins. Eventually, though, in the very early 1980s, Reed bought the building outright. And Reed came from a wealthy family, even before any patents or other sources of income he may have had–which is why he was able to afford to construct his own rocket.