It is a tough life, living in a doer-upper. We did our last house almost completely by ourselves - I never thought I would become so proficient at tiling but I have to say that I did a bloody good job!
In the end, we moved as we had made so many mistakes and frankly couldn't deal with fixing them ourselves. We took a haircut on the price (we made money but locally houses have sold for much more than we sold ours) to pass it on to someone who would have the energy to make the changes needed.
So, I counsel you this - do things in the right order. Retrofitting repairs is always more expensive and convoluted. Here is a personal example:
We lived in a victorian house which had dodgy stairs. We decided we'd sort them another time. By the time we got to looking at that we'd have needed to changed the floors, a doorway and skirtings. That skirting might have pulled some of the plaster off, which means patch repairs.
What could have been a relatively simple carpentry job turned into a much bigger problem by leaving it.
I have loads more of these examples - I can't even tell you! My top advice is to think about the order of your works and if you are budget restricted live in a crap hole and get the fundamentals done.
Electrics and heating / plumping can be very disruptive to do later down the line and are central to making a house comfortable. Leaks can also be lethal - we didn't realise we had rot from a bathroom leak when we first moved it and had to rip out a load of concrete in the floor which was a horrible, horrible job.
Next but equal - make the house water and air tight. Fix any cracks in render / repoint where you need to. Reseal windows, inside and out. Get new chimney pots if you need - those are so often the cause of bad damp in chimney breasts and it makes an older house feel and smell horrible. We didn't do ours properly at first and every time we had bad wind it whistled through the house and made it smell.
Check all your guttering and fascias. They might look OK at a glance but they might not be - often they need cleaning and while you're at it you notice loose screws and stuff which you should fix before they before a problem.
IF you have to pull down ceilings, do it before doing any ealls. We loved with unplastered ceilings for ages and it was fine. They are so messy coming down though, that you want them down before you put in any other effort. Also, taking them down after you have plastered the walls will cause damage to said newly plastered walls, which is a waste of money and effort.
Final thing is, if you can only do a couple of rooms then do your bathroom and bedroom. Having a nice bedroom to escape the horror is essential and being able to take a decent shower / bath after a long day of DIY is bliss.
We are totally bonkers as we are about to start another renovation - this one even bigger as we've bought a pretty much condemned house (why the devil not, after all!). It wasn't even that cheap as we live in an area that is very hot. But you can make it what you want if you do it yourself, so there are upsides and it definitely does get better. It just takes a while. Good luck