Lease And/or Mortgage When Buying

Scenario

I am buying a house in Pattaya for my Thai wife and our son. The title deeds (chanote) will be in her name. For my own protection, I have had conflicting advice about arranging a lease and/or registering a mortgage against the property.

Can anybody please confirm that:-

If I arrange a 30 year lease, at the same time that the house purchase is completed

a) Legally I cannot be forced to vacate the house (for 30 years).

I can say who can live there.

c) Lease dies with me.

And finally d) However the house could be sold to a third party if my wife needed money for some reason.

If I register a mortgage against the property.

a) this is recorded on the chanote, and the house cannot therefore be sold without me receiving the sum involved.

the mortgage can be willed to my son.

But c) I don’t have any legal control over who lives in the house.

The 3rd option is to have both a lease and a mortgage against the property, although this doubles the expense. Has anybody done this?