i have a 1978 rv, it needs a back brake line put in, How much will this cost me? Also it needs a tune up,?

Question

How much will that cost?

Answer 1

Steel brake lines are cheap. The pricey part is the labor.
It's a little time consuming "making" the brake line the right length and with the proper bends in it.
Bleed the brake system.

The flex lines can be expensive $30 each. (give or take)

A tuneup on a Chrysler bigblock $70 in parts.

Total should be around $400.00 parts and labor.

ADDED:
Unless the y come across something weird.