The use of a hydrometer, except in the case of a new brewer, is highly over-rated.
As Uncle Charlie says, "R, DW, HAHB!" (Relax, don't worry, {and} have a HomeBrew!)
If you're a new brewer, and your stuff is in the fermenter, wait a few extra days (after you think the ferment is over) to ensure fermentation has stopped, before you bottle.
Or, save up the required $6, and get a hydrometer.
steve