I would say it depends really on your state they recommend a middle score of 650 BUT that doesn't mean it would be a no for you necesarily.....One thing I will add is I would make sure your DP is 20% or 25% depending on your state so that will save you a BIG chunk on your monthly payment 
I didn't have a whole 20% for down (for my state) and it was almost a 600 addition a month but when I do pay the house off I will see some (not all) of that back so be mindful of that 
When I checked with my realtor and finance person (sorry don't remember term for him) they pulled the middle score on my mortgage scores here and it matched perfectly mine was 711 at the time Your income will definitely help you as well
If you do have time I would defintitely see about getting those removed if you can pay off the one and see if you can pay and get rid of the other collection (collections will always hurt your score and if you can jump your score if you have 2-3 months) that will make a difference in the apr for your home which can save you thousands
Yes but be sure you are under the MORTGAGE FICO you don't want to be on the one that is used for Bank/Cards or the Vehicle score you want to make sure your MORTGAGE one is at least 650 or higher for better rate/deal if you can ideally hit that 700 middle but I'm not sure how soon you are wanting to buy?!
So when you sign in to your FICO on the main page where it shows the first set right under it it will say "View additional FICO versions used for Mortgage, auto and bank...." Click on that one when I click on mine it will show you Experian as the main one but Mortgage is at the top left right under bold print
"Commonly used in Mortgage lending" and then you can use the tabs to switch to Transunion or Equifax to see what theirs says If you don't have the one that shows all 3 please get that one to keep a better eye on it until you get your home then you can 'downgrade' to one report or the once every so often report
I would make sure your Down Payment is 20 or 25% depending on New Hampshire it may not be that high I know for Ga it's 20% that they ask you be at 'ideally' to help save you on your monthly payment so find out what NH is But you go based off the amount of home you want that you would qualify for so if you are shooting for 440k (I think that is what you said sorry) then calculate 20% for DP off of 440k which is 88k for Down Payment! But that is IF NH is 20% that may be a state that is lower or it may be higher like the 25% not sure sorry.