what are you talking about.... good lord... just a bluetop 4age would be like $500 max for a low mileage JDM motor..... lift up the car, drop the motor out, swap out the accessories & the manifolds (if you wanna keep the EGR), and slide it back in... will BOLT right in and work off the stock ecu
i bought my mk1 in quite the opposite shape.... body is fair (few dents) but has rust and NO interior... but awesome running new motor... & i got it for $200
it's a very fun car to play with... but kinda sucks to work on... everything is somewhat difficult to get at.... fun to work on at the same time since it's not my daily driver:
motor when i bought it:

not gonna get into it, but previous owner put new motor in and had a "cooling" issue after the new motor was put in which i found to be a coolant reservoir bottle cap hooked up
backwards

a week later (internally the CLEANEST 4age i've ever seen. period.)

^^ seat has been swapped for a cheap old raceseat
either way, i got mine for $200 and couldn't be happier with it