
My experience of this op!
I do have the same breed as you - but have never had a patella problem in a Chi! I do think we have differing experiences, depending on breed size though.
However, I had a Toy Poodle that needed the operation - this was many moons ago. I lost her 18 months ago at 17 years, and I have never for one moment regretted surgery. It was the best decision for my girl. She could still do a standing jump to my shoulder at 14 years. Although I wish I had not had the operations so close together. She was 11 months for the first op, and my vet at that time wanted to do the second op 6 weeks after. I know you say that you have been told to rest a month - I am horrified!

I have , 10 days ago, had a very small Yorkshire Terrier undergo this surgey. She has to have CAGE REST for 12 weeks, before attempting her second operation.
I know that someone has said that this is an easy operation.
It is not! The girl I have just had done was the most difficult that my vet had ever seen. He admitted that if it had been at the start of his career, he would never have been able to work his wonders. Every vet that I work with tells me that it is
major surgery. Sorry to disagree with someone, but I have heard of so many that are not straightfoward, and need an orthopaedic expert. (Just glad I have got one!)
I would most definitely take advantage of the financial help, I know that £700 per leg is pretty average. And the younger your girl, the more success, as she should sail through it. However, due to the nature of the surgey, you can do huge damage and rip the pin out if you allow any sudden movements (it's why my girl is caged, as she wants to race like a loon, and she could do untold damage.) At £700 it seems daft to undo all the vets work. If she carries on being a tornado, I shall end up nailing her feet to the floor. :-) I have to put her lead on for a wee, as she would be running like a maniac.
I would definitely leave 12 weeks between operations personally (I have asked loads of vets what they recommend.)