So if the unit is somewhat working that is a good sign because it may not require major expenses.
Much emphasis primarily through the internet and YouTube suggests that in order to have good quality sound from your vintage receiver you must replace “all” capacitors is not true. “If it is not broke do not fix it”.
Most repairs may require a replacement of electrolytic capacitors in the power supply, some lamps and cleaning/DeoxIT and lubing the controls and switches.
It definitely depends on the unit condition. Receiver that stored for many years most likely will need less work.
Others were running constantly in a closed environment which makes many capacitors go bad capacitors do not like heat.