Your MBAM log is clean, but Essexboy will continue working with you when he returns to the forum as some tools he uses he also may need to remove from your machine and clean things up. He will also instruct you on "How you got infected" in the first place.
Once everything is cleared up, we can address your issue of how much and what software is needed. It is true that you do not want to have too much to conflict and overkill, but you can also layer your software for defense. Since you now have over 20 posts, can you enter your Signature so others can assist you with this. Please go to PROFILE on the top of the main forum page > Modify Profile > Forum Profile Information > Signature. Enter information about your system like the Operating System (OS), RAM, browser, security software, what version and product of Avast and firewall you use and other items you wish to mention. See my signature or others as an example.
As for a firewall, there are several that are compatible with Avast that you can do a search on the forum. Some that have worked well are Online_Armor (free and Premium), Outp0st (free or paid). We have recently noted problems (on their end) with PC_Tools; and have noted problems with Ashamp0o, and some have had problems with ZA. I would suggest doing a trial for a month after everything is fixed on your machine to see if a software is compatible with your other software prior to buying anything. But before doing any of that, we need to continue fixing your malware problem first.
