Active job

Reseal or replace?

I'm looking for someone who can provide me a quote for both simple window resealing and also a quote for double glazed aluminium inserts, as we want to compare and decide which will work better for us price wise in the long run. We also have French doors that we are looking to replace with a double glazed sliding door. Please note that the windows we need doing are all upstairs, and depending on price will most likely be looking to get windows done individually as budget allows. Thanks!