It's not hard to mix your own. Easier than making bread from scratch.

The chemicals are a lot safer than what is under the kitchen sink or in the laundry room (or, heaven forbid, the garden shed [even worse, the garage]).

You can get a perfectly adequate little digital scale for less than $10 on Amazon. Actually, you can use measuring spoons to parcel out the chemicals with no ill effects, other than driving some APUG posters positively livid.

Very good developers can be concocted from vitamin C

Coffee can be used to take the place of metol/phenidone - making a developer called Caffenol-C

The washing soda in the recipe can be made by heating baking soda in a 200F oven for an hour.