Re: Is a big jump between DSLRs
"The amount of money you have to spend to get a significantly better DSLR as compared to an entry level one is large enough that I have not bothered."
That's because they're significantly better cameras. You get what you pay for.
"They do not keep their value"
Then you've just answered your own problem: Buy second hand. Ideally just before a major Nikon/Canon high-end release when hard core 'must upgrade' photographers are foaming at the bit and trading on their older model.
"and having the right lenses for what you are photographing is more important. I can't afford them either."
Lenses hold value, but once you decide who you prefer in the brand wars, they're an investment that will outlast your next couple of chassis, assuming they are well looked after.
"I had to use a 50mm f1.8 for almost two years manually so it taught me a lot about getting the right shot."
Nothing wrong with a good prime lens. Pro lens of choice for many applications. they also encourage photographers to move around to compose, instead of welding their feet to the spot and using zoom.
Biting the hand that feeds IT
