Financial requirements help !!!!!just dont get it!!!!

My wife’s previous 2 spouse visas were easy with regards to getting through the financial requirement but this one is much harder and I desperately need some help so I can sleep again.

My wife’s visa runs out on 26th October 2019. She will apply for “ILR” indefinite leave to remain.

Last September I lost my job and basically we have both been studying for new higher paid careers.
We have a 250K, 3 bed house that I paid outright for 4 years ago and we have 13k savings in the bank. We In the real world we are extremely secure but not so secure looking at this VISA financial requirements..

Our 6 month countdown is between this April- October. I had originally planned to re-mortgage the house to put money in the bank for the 6 months but I wont be able to do this because nobody will give a mortgage to somebody that hasn’t worked for 3 -6 months previously. This creates a massive degree of uncertainly and risk for us and I wondered if somebody could look at my new plan that builds in contingency just incase our employment earnings don’t quite get to the required £18,600 threshold.

GIFT and SAVINGS:
My wife/spouse will fly to China to receive 20k as a gift in in a newly created bank account put in her name.. The family member will get her a letter to say it is a gift.
Therefore with my own savings of 13k and his GIFTED cash that will mean we have savings of 33,000k. The 20k gift will be under my spouses name in a CHINESE current account which will have a bank statement within a month submitted.
This is path acceptable and have I figured it out perfectly?
MATHS: This will take it down the threshold down by a total of £6800 so we will now have to earn income of £11,800

RENT a ROOM:
I will have a lodger in our 3 bedroom house who will sign a 1 year rental agreement between this April to April next year. He will pay rent of a total of £600 per month. I believe this is calculated over 12 months therefore 12 months rent would equal £7200 income for the year.
I will get a letter from the “estate agent” to inform say the house is big enough for multiple occupants and that it is a 3 bed house etc. My bank statements will show the income for the last 6 months between April and October and will back up the rental agreement in place.
IS PATH CORRECT? Have I missed anything?
MATHS: So as previously worked out with the 33k gifts and savings that brought the financial requirements down to £11,800. Room rental will bring the requirement down further so we will then have to have a salary of £4600 between April and October to cover the rest?

INCOME THEN NEEDED WILL BE: £4600 gross income needed to be found between April and October ===???

Please can you tell me if the RENT and GIFT/SAVING’s route I have planned in an acceptable path and will work with no come back?
Is our maths correct?