Help needed with Cash Savings route for Spouse Visa

[aliclan000]

First time poster, apologies if this is in the wrong section. Would really appreciate any and all help regarding my situation.

I recently got married in Bangladesh and am hoping to bring my wife over on a Spouse Visa. She has the necessary English requirements but I am needing to meet the financial requirements.

As I am completing my PhD at the moment I am unable to to show the necessary £18600 pa. However friends and family have offered to borrow me money to add to my £15000 in savings so I can apply through the Cash Savings route.

1) Do I need to show proof of where the money came from? If so how?
2) Do I need to explain why the money was given to me?
3) What must I do once I have the £62000 in savings?
4) How should I go about applying for the Visa once the money has been in the account for 6 months?
5) Finally is it worth hiring an immigration solicitor or is applying through the cash savings method relatively straightforward?

Apologies for asking so much but would appreciate any and all help with the matter.

Many thanks in advance