Membership Pro - right for us?

"..purchase it, try it to see whether it meets your need or not..."
We want to know it will suit before purchase - not try it and see....

Re :
1. Ability to make a voluntary, user entered donation amount on joining, renewal, or at any other time (Including by non-member of public without signup)

2. Member ID - whilst our format has been an incremental number plus member initials, the initials is not a requirement.

3. For those with no email - we would still prefer they be assigned a system generated email address on signup - memberID@ourdomain.com

Are these all proposed part of the customization?
If we purchased today, could the required customization be completed within next fortnight?

1. Ability to make a voluntary, user entered donation amount on joining, renewal, or at any other time (Including by non-member public)

=> You need to create a custom fee field. No need for customization but you need to read document to understand how to setup a custom fee field and setup it

2. Member ID - whilst or format is an incremental number plus member initials, the initials in not a requirement.

=> That's supported by the extension b default

#3=> Yes, need to customize. What's memberID ? Maybe should be username ?

#4 is the same with #1.

I don't know what's next fortnight ? How many hours ?

memberID - yes, same as username...

A fortnight means two weeks - 14 days...

"..need to read document.." - yes, you have really good online documentation

Ah, We don't need that much time. Only 3 or 4 days is enough

"memberID - yes, same as username..."

So we won't want users to set or change this themselves..... it is fixed

How might these customizations affect future updates?