When someone is considering offering their services, they can use [ageru], which is usually the translation of "to give" (transitive verb here).
See the examples below.
Most of the time, people use it combined with the [-て] form.
Because of the nuance it adds, it's a one-way verb to use : this form is meant to humbly express yourself to someone.
The honorific way could be like this : 貴方の為なら、何でもいたします。 (Anata no tame nara, nan de mo itashimasu.) I would do anything for you. [liter. "if it is for you, I shall do anything"]
(it's a very basic note ; please check [kureru] and [morau] to get a better understanding of the usage of these verbs)
#566 Add "。" at the end of the sentence.
#3727 No error, but there's no need to say "あなたがたの."
#3728 In this example, I would say "あげられる" instead of "あげる."
#3729 No glaring error, but... あなたに代わって、買い物をして、家を掃除して、夕食を作ってあげる。 This must be easier to read.
#3730 I would say "そのうち" instead of "いつかそのうちに."
The other examples sound good.
Hey Nick, I think its great your talking the time to error check the examples, but I disagree with your suggestion for [ex #3728]､ It doesn`t seem natural to use the potential form of a verb in this manner. I think its more natural just the way it is, but I would lose the あなたに. since the verb あげる is a one way verb the person you are talking to is already implied and あなたという言葉はあまりいい感じじゃありませんね.