"economical" has no comparative or superlative form. You would say "more economical" or "most economical."

They have a fair economical condition, or they have a hard economical condition.

It's missing an adjective for the noun 'economical.'

When "economical" is used as a preposition it is correct to say : They have an economical condition, with the meaning of profitable.

Broomboom provides the best private taxi service in Kolkata. It provides services at an economical price. In its cab, there is a facility of 24x7 camera and audio enable feature.

The nouns related to the adjective 'economical' are economics and economy.

Benjamin Franklin was the author of 'An Economical Project.'