Deed

1a. She’s always helping people by doing good deed.
1b. She’s always helping people by doing good deeds.
2a. The land was transferred by deed.
2b. The land was transferred by deeds.
3a. The deed of the house is missing.
3b. The deeds of the house are missing.
Please correct all.
Thanks.

1a. She always helps people by doing good.
2a. The land was transferred by executing a deed.
3a. The title (deed) of the house is missing.
3b. The title deeds of the houses are missing.
(others, to me, do not look acceptable.)