Lewis Carroll would love this variation of his ingenious Doublets game! Word Origami permits letterbanking, as well as letter swapping, so source and target words need not be of equal length. 

Change PARTY into FAVORS.
Par = 9.

a. LETTER SWAP: change one letter of the word to produce another [1]
b. LETTERBANK the word into another [3]

Each step must be discrete; you may not combine two transformations into one step. Newcomers to letter banking and Word Origami strategy may want to visit page 80 of The Vocabaret for Rosemarie’s Guide to Solving Word Origami puzzles.

Spread the good words,