2000 century custom battery drain

I Got a 2000 century custom and has a battery drain overnight
Bought a new battery when I went to the parts store had them check and said replace battery so did that
Went to get in to go to work the next day and hard to start.went to work and stopped to the parts store after had them check it out again.This is the read out they gave me

Battery test
good battery
voltage 12.60v
measured 807cca
rated 700cca
temperature 108 f

starter test
cracking normal
voltage 11.13v
amps 199.5a
time 1.48s


charging system
no problem
no load loaded
13.93v 13.85v
11.3a 8.4a

charging system output test normal

drain test
results
0.82a
suspect

so what would be draining this all of a sudden
I took my trunk dome light out
took out my radio fuse
took out interior light fuse (so no lights light up inside car)
took out heated mirror fuse
And left them out
still a drain
what would cause this it is ever so slight should I pull out all fuses and put back in 1 by 1
Thought about disconnecting the drl's but can I do this?
At a loss any help is greatly appreciated

If you have pulled all those fuses there may be an issue with the wiring from the battery. Check the connections at the starter solenoid to make sure that they are tight. Also check the red and black battery cables to make sure they are not internally corroded. This can prevent good voltage transfer or a lack of proper charging to the battery.

Thanks I will try that in the morning dark out now.guess I can put them fuses back in after I check that kinda hoping it was going to be simple but never is will let you know Thanks for the quick reply

hi,Sorry for not getting back till now had a family emergency
any way I took the battery cables off the battery and the positive had some corrosion on it cleaned it good and car runs great you think they would have said something when they put the battery in
as with the starter solenoid looked at it and does look dirty What is the best way to clean around there?What should I use in other words
also what is the best way to clean the engine without interfering with all the electrical components and stuff.Thanks

Clean the starter contacts with spray contact cleaner. It leaves no residue and will clean off any dirt. As for the engine you can use simple green and a high pressure hose just don't use a steam cleaner. I would also cover the coil and ignition module with a plastic bag and don't spray with extremely high pressure as you may damage the plastic lines.

Well I'm back to no start in the morning again .A man at another auto parts store told me to take the negative cable off and leave it off over night and if it does start its the battery not electrical I did that and it didn't start took the battery back to the store and they checked it and said it was good so don't know if this man knew what he was talking about or not
came back
voltage:
12.58 v.
measured:
872 cca
rated:
700 cca
temp:
73
They say its the starter that is bad car does have 96,000 miles on it
so guess I am looking at a starter Are they kinda easy to take off and reinstall? Thanks